Simple and far more elegant solution: let us store save data on game cards for physical releases.
There, you solved the problem for people like me.
I assume that they're looking at online save backups as a potential value-added service, like a certain something The Pokémon Company runs.

I WON A BET AGAINST AZUREN! WOOOOOOOOOOAAAAAAAAHHHHHHHHHHHHHHHHHHH
:3







