About "LaTeX hiding TeX from your thinking": In my humble opinion the terminology introduced and coming along with expl3 does another one. :->
I fully agree with you that you have to understand TeX in order to be able to use LaTeX in a really well-versed manner.
But someone who has to cobble together whatsoever paper with LaTeX on a one-off basis, because some profile neurotic instructor at university absolutely wants it that way, and for whom it is foreseeable that s/he will never use LaTeX again afterwards because in practical life everyone works with Microsoft stuff anyway, gets that as long as s/he has someone on hand to help her/him every now and then, even without knowing all the subtleties of the TeXbook.
But someone like that has to be able to live with the awareness that, from a TeXnical point of view, her/his work is not an elegant masterpiece, but something that has somehow been put together.
You ask very personal questions:
Do your activities at TeX.SE steal too much time from your real life?
I wouldn't call that "stealing".
This is because the consent of those from whose property something is taken does not play a role in stealing.
As far as my dealings with this forum are concerned, I don't see myself deprived of deciding myself about the amount of time I spend here. (Keyword: Self-determination.)
The words "temptation" or "seduction" might be more appropriate.
In my case, however, "temptation" or "seduction" are not that much due to deliberate (subtle) manipulation by this community or its framework with the nice reputation game and badges, etc., but more due to my own desire to find diversion and distraction from other things, and sometimes to find recognition.
If this community did not exist, I would probably find something else to distract me from these other things, and to seek/find recognition, which would then take the same place in my real life. ;-)
I know they are common parlance. Nevertheless I have problems with phrases like "real life" or "virtual reality", which you encounter everywhere these days:
From what other kinds of life is the word "real" supposed to differentiate a so-called "real life"? In what way is this differentiation important?
I consider my whole life to be real. Otherwise, it might not come to the point sometimes that things involving concepts like virtuality or fiction bother me in a very real way.
(I am now trying desperately to present my point of view in a short manner without this distorting the gist of my thoughts - you know I'm not good at that - should it go wrong, I hope that at least the goodwill is evident.)
When I become aware of aspects, this becoming-aware in any case is something real. The effects of this becoming-aware, e.g., the effects on my well-being, are real, also.
There are several possibilities for initiating a process of becoming aware of whatsoever aspects. With a subset of these possibilities starting points for the process of becoming aware can be the "activities" of sense organs/perception organs, which deliver to the information-processing-system "brain" connected with them information about perceptible "things" lying "outside".
The perceptible "things" can be both real and have properties related to "virtuality" at the same time:
Virtuality is the property of a thing not to exist in the form in which it appears to exist, but to resemble in its essence or effect a thing existing in that form.
This definition also subsumes the following case:
The property of a real thing not to exist in the form in which it appears to exist, but to resemble in its essence or effect a (different) thing existing in that form.
(Someone might ask about non-real virtual things:
The holodeck from Star Trek, which can represent pretty virtual three-dimensional objects that look like something, although according to the story they are just some photon conglomerates, does not really exist, but exists only in fiction. When you refer to these pretty three-dimensional objects, you refer to fictional virtual objects, not to real virtual objects.)
Do you feel that you are absorbed by this site and your normal activities are faded?
A fundamental question (also) in dealing with "social media" is:
Does one spend one's time on social media intentionally and voluntarily and with pleasure, or is one taken in by all this in a way that is actually not good for one, that one sometimes even feels as an impairment of one's freedom of will or one's own control of one's own life?
If that is the case, it might be good to get to the bottom of why one is putting up with this.
The medium itself, in which one spends that time, even though one is uncomfortable because of the time involved, and even though one could perhaps do otherwise, should not necessarily be the appropriate point of contact for this, because aspects often play a role that are to be located elsewhere, and whereabout other people know better.
I don't take my activities on this site for abnormal (although others might not agree in this point ;-) ).
The thinking about questions and "macro-puzzles" indeed sometimes absorbs me in a way where other things appear to be in the background.
It also happens that I get "carried away" when I try to explain to people how things work in TeX and LaTeX and how the different components / stages of processing intertwine.
But since I know that this can happen to me, I only go to TeX-LaTeX StackExchange when I know that it won't hurt if it happens to me, because the window of time in front of me is big enough, and the other "fading activities" are not really important things, but things where it won't throw me off track to postpone their getting done a bit.
Let's make an analogy between this site and a forum (marketplace) in the Latin sense of the term:
In my opinion it's a nice and rather comfortable marketplace with lots of Markdown features that I've come to appreciate. E.g., inserting code-snippets and images and the like is easy. The user interface is straightforward. Pleasant to use. It is easy to find your way around.
But I am not "absorbed" by the look and the features and the comfortableness of the "marketplace". In case TeX LaTeX StackExchange would cease to exist, I would not feel this as a great blow of fate. It wouldn't be nice, but I wouldn't have a big problem with moving to other places where TeX/LaTeX is also discussed, e.g. back to usenet, to comp.text.tex/de.comp.text.tex, where unfortunately there is rather little going on at the moment except for announcements.
I am fascinated by the "goods": I am fascinated and thus sort of absorbed by the questions—like a chess player who is not fascinated by the room where s/he plays but who is fascinated by the challenge provided by the game itself and by the tricks/techniques she/he learns from the other players. (Btw: I have often learned new tricks for using TeX from the code you have written, and in such moments my heart has leapt.) Seeing/learning how others program is sometimes of similar fascination to me as the fascination of someone studying the elegant movement of a panther. Even if I can never achieve that elegance myself, it's still "real steel" and an honor and a joy to witness it.
I do not think that for all people the boundary between normality and abnormality of the extent of their activities on this site is the same.
Whether the extent, be it normal or be it abnormal, is harmful also plays a role.
E.g., whether the extent causes one to mis-prioritize other aspects of life.
That in turn also depends on the living conditions. And whether the purpose of being here has to do with escaping other aspects of reality. And whether escaping these other aspects of reality for a little while is a good/recreational thing or whether it is a bad thing because the extent causes disregarding the need of improving living conditions and/or causes deterioration of living conditions due to neglect of other important aspects of life.
When I'm here, I'm distracted from my state of physical health. At the moment I don't see any possibility, which could be restricted by my being here, to change it. So it's more of a good thing for me to be here and to have the feeling (hopefully not just the illusion) that I might still be useful for something.
Do you spend too much time in front of your computer monitor with TeX.SE open?
Definitely yes. E.g., when watching a video on YouTube while having forgotten to log out from TeX.SE. ;-)
And from time to time, yes, when I am carried away by some intriguing macro-puzzle, or when I am carried away while writing about how TeX or LaTeX works. The process of learning how to explain things/how to word things so that they are more easily understood correctly is both fascinating and terrifying to me at the same time. Terrifying when I realize how awkward and incomprehensible my previous attempts have been and that my current attempts are just different but not better.
When I sit down and write an answer, it happens that at some point I realize that I should have eaten something long ago, or that my bladder almost bursts because I have not paid attention to the signals from my body.