As someone who has been here since 2014, I very much agree with that post.
Some more thoughts from me: Both the forums and the Answerhub were great places around 2014/2015/2016. Back then, when Epic introduced UE4, they seemingly had a great concept for how the community and support should work. But more recently, it felt like Epic more and more moved away from that original concept and replaced it with no concept at all. One example is this new forum software. It generally feels like some mobile website on PC, a lot of screen space is wasted, scrolling through threads to find something is way harder - so this new forum is way less usable than the old forums, and now every time I find a forum thread when googling for something, I tend to not even try to find the answer somewhere hidden in that thread, it’s just too annoying to use. The new forum software kinda killed the forums for me.
Another point is that back in 2014 and, a lot of devs from Epic were active in the forums and answerhub, answering all the highly technical questions that no one else could answer at that point. It stayed like that for a while, but more recently, involvement from Epic staff has been way less in both places, leading to many very technical questions never being answered. That drives away the highly skilled people who are primarily interested in highly-technical questions, and leads to places being occupied primarily by people new to UE4.
Now in 2021, if I have some highly technical question, I know that digging through the engine code is the only way how I can find an answer for that, so that’s what I do, I don’t even try to post it on the forums or answerhub. The engine code can answer all questions, but it’s not necessarily fun to have to search for hours through engine code if someone who’s familiar with the code could also just answer your question in 20 seconds, and it’s wasting a lot of time if everyone who has a highly technical question just searches through the engine code on their own instead of it being posted on some Stack Exchange equivalent where it would accumulate upvotes over time and ideally being answered by some Epic staff at some point so that anyone in the future who has a similar question could find the answer with just googling it, instead of also having to spend hours digging through engine code to answer themselves the same question.