Well let's say tomorrow we wake up and find to our surprise there is a new forum called CD players. It is of course empty and likely to not have very much for a good while. Now someone comes along wanting to read about a certain cd player but doesn't see that there are now 2 different places to look, the place where it was and the place it is now. That is 2 forums in reading about cd players. Now I suppose that they could spend days going through all the old cd player threads and manually move them to the new forum ,but that would take too much work. But to do less would indeed be the "messy" housekeeping that you think is there now.Confusion? Why would there be two separate forums?
There are lots of reasons not to create new forums. One would be not fixing something that isn't broken.
There are actually lots places where there could be an argument for creating a new forum on AK. Take speakers, why isn't JBL there with a forum of its own? Biggest speaker company there was for decades and not a forum dedicated? What's up with that? Of course there is a good reason, it has its own forum already dedicated to Lansing speakers on another site, and I suspect it would pull people away from there to AK,and sometimes the ends don't justify the means.
Let's see what else needs it's own forum.. How about Bose? Or here's one, speaker cables and interconnects. We all use them and scarcely a day goes by when there isn't a thread started somewhere here on them. Wouldn't it be neater if we could simply pigeonhole those threads together? I think not, the home page would start to take on the look of something rather ungainly and take a long time to load and scroll through with everyone's pet forum represented.
You asked, I could go on but I won't. Doesn't matter anyway, because this site and most others are not ran by polls or concensus so quite likely a moot thing.