Current generation? Distributing ROMs and claiming it's fine goes back to the early days of the web. They even had disclaimers that said "This is legal if you already own the games."
By "own the game" they mean "own a license to play the game". Why should ROMs not be legal if you already own the cartridge?
You'll have to ask a copyright lawyer about that one. Every single one of those games had a notice somewhere in them saying not to copy them though.
Owning something like 5 copies of A Link to the Past, I agree with this sentiment (the format-shift argument), but I don't think it's proper justification for distributing them. As much as I'd argue it's fair for those who have paid, we can't ignore the fact that most people haven't.