I wanted to know where LaTeX is lacking with the idea that I could develop patches for it. I believe, it is not an opinion based question. Definitely, whatever developed, will have room for improvement. However, the question was put on hold (closed) as being "primarily opinion based". Another question of similar nature was posted a while back. I believe that post is definitely opinion based, since each user possible answer will be based on the user's comfort level and the Operating System they are running under. It is definitely opinion based but it was upvoted by many and my question was not. How can this be explained?
The primary goal of all Stackexchange sites is to become repositories of reliable information on whatever topic they cover, in our case, TeX, LaTeX, ConTeXt and their relations.
To this end, questions whose answers can't be given definitively are not good questions as regards to the goals of the site, and are therefore closed. Now your question is by definition opinion based, since it is asking a negative: what is missing from TeX? There is an arbitrarily large set of answers to this question: TeX lacks all sorts of things: it lacks grid typesetting, it lacks HTML output, it lacks a built-in implementation of
emacs and it also lacks an interface to my home thermostat so that I can control my house temperature with it. Now these latter two lacunae you may say are ludicrous, but that's the point: that's your opinion, and who is to decide?
Now we have had some similar questions in the past, but crucially they have been stated in a more positive way.
The question you link to isn't really similar, because it has a definitive answer.