Yeah, I made this theory a while back, almost exactly like this. But oh well, I think that thread died.
I don't think this is the end at all, they're makin' too much money & have to large of a fanbase to quit now. Gen V will be a reboot, HG/SS is just to give the hardcore players the nostalgia trip they need, let newb players experience Johto, & to tie up all the loose ends so they can have a clean slate with future generations.
Besides, the anime director said there will be a Gen V.
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