Their is truth to some of your statement, and def not getting on you, but I just don't see that happening. If you've been around long enough which I think you have, then you remember the ups and downs since the early 2000's. IE shoes being on clearance and other places for the low only to rise back up again. In my own opinion I don't believe shoes can ever really be non existent cause I'll always need something on my feet. However I could care less if any of the kicks I purchase are mainstream. Been copping kicks since before social media and all the magazines jumped on the train. Worse case the kiddies eventually have to let their collection as you call it go and I'll swoop in like it's an undervalued stock and grab it for the low anyways. You would be better off thinking years down the road the next gen will have someone near an MJ to try and influence and do what he did for the game as well as kicks. (No Kanye doesn't count and still doesn't come close). Will be hitting the mall for tkts and some auntie Anne's.
Stay thirsty my friends.