Top Reason in my book, plus from speaking with other old timers.
1 Economy, people just don't have the money to be dropping on games, and upgrades for the fix and repair daily AEG's.
2. CBSA crack down, and loss of critical retailers, combined with stricter ant-gun policy.
3. Old timers are burnt out, and have priorities that they neglected before and are now on the top of their to do list.
4. The wearing down effect of added cost & aggravation of constantly fixing over priced low quality products from Asia. Especially in these economic times!
5. And of course, Crapsoft & Clearsoft undermining game play. This also undermines the quality of AEG's. Also from I have been told even when buying good internals has been going down as well. Not to mention the constant new companies popping up from china, and there endless clones that only hurt the more reputable, and named manufacture's. Airsoft should be improving in quality, not going the other way, although from what I have herd, and seen now is that some of the newer made AEG apparently are getting back on track. ( Gun doc's knowledge needed)
These are my opinions combined from others I have spoken with have said about the community & game play.
My personal prediction is as the economy sort's it self out over the next few years, things are going to vastly improve into another "Airsoft Golden Age".
This depends on the economy improving, and no more increases of restriction from CBSA or government, but don't count on that, if anything they will increase the restrictions.