Unfortunately, I don't see any evidence of that. BTW, you seem to assume that people left in a huff. Speaking for myself, there was no "trigger event" that made me quit posting. I was never upset, I just quit spending so much time here before all the changes. Yeah, I know people have always complained that Goob did or didn't do that, but I never gave a **** about any of that. In fact, I thought it was funny that the owner of the site would do things like hold mod elections and then never bother to put the winners in their positions or offer any kind of explanation as to why he wasn't. I thought it was even funnier that he actually got input on the mod-elects from the very mods they were supposed to be replacing. The dysfuction was just part of the lols.
The thing is, this was a pretty good forum for car audio during the time period you say was so bad. It always seemed obvious to me that a good portion of the members stopped by initially for a little help with a system they were building and then stuck around for the entertainment. The people hanging out in the lounge would then pop over and read / post in the technical threads. Some of those people gained a fair amount of knowledge and passed it on to newer members. You also had some of those people building new systems, trying out new stuff, where they likely would not have had they just stuck around to have those few questions answered. In short, the Dome fed the technical side of the forum.
Also, I think you are overstating the case for trolling in the tech side. Sure it happened some (as it sounds like it does now), but it really wasn't the problem you make it out to be. It sounds to me like there is some revisionist history going on.
Is it a better place for car audio discussions now? I have not been around enough to really say. I can tell you that it's obvious to me that traffic is way down on that side as well. If I had to guess, I would venture to say that it was better a few years ago. In any event, it doesn't really matter to me one way or another -- but good luck.