The Tips & Tricks section is split up into specific subsections like this, because it's already known exactly which subsection each topic should go into, and if you're looking for info on a specific topic you can more easily find it that way.
The main Tech forum is not split up into subsections for a few different reasons. One is that the person in need of help won't always know which area their topic should go and would very often choose the wrong one, so we'd have to move topics around too often. Also, topics may originally be started in the correct section, but it turns out it's actually something else, or it falls into multiple categories. Then what?
Another one is that there just aren't that many active users here at any given time, and it's a lot of extra effort to click through multiple sub-forums just to check on what few new threads there are. Many people won't bother to check all of them, so a lot of posts will be largely ignored. I can't remember for sure because I've been on this forum for over 20 years in all its different iterations, but I believe we tried something like that for a while, and it just didn't work.
This forum has been around for a very long time, and a lot of different things have been tried over the years. When considering the available resources for the forum and the needs of this community, what we have now is what works best.