The problem with that is people will have had to back up every individual update ( or at least the ones people will wanna play most of all at the bare minimum ) and find ways to make both java and bugrock edition work without need for an account if mojangles and macrohard ever decide to axe the game at any point.

I have no doubt the majority of updates have been backed up by some data hoarder for Java edition, but I don't know how that would work for bugrock edition.

Never be too sure about "will definitely be avalible". Microsoft/Mojang is doing evreything in their power to lock minecraft down and end the days of mods, backward support, and buy once own forever.