When I did my squadron rotation, it really opened my eyes to different styles of gameplay. Without exception, every single squadron I visited was gracious and the cohesiveness within the squadron was readily apparent. Some squads based themselves on unit tactics, some on a particular style of gameplay, and one squadron was a strict Luftwaffe group, and some did whatever they felt like at the moment.
I wish I had time to continue the squadron rotation, I just can't do it while spending time in the TA and remain happily married. I'd really like to see someone who has been here a few years with a little bit of writing ability restart it, I think it added a lot to the game.
Back to the topic on hand, I don't feel squadrons are on the decline, but some are a bit less active than they used to be. It is the ebb and flow, eventually all groups see a decline in their lifetime.