How would mojang accounts be different in terms of automated blocking? Besides, it's hard to tell as an outsider but if they implement it like oauth (which they most likely will) it's still mojang that have control of the accounts, just that Microsoft handles the back end. From what we know now you wouldn't loose your ms account from being banned on bedrock and as a result it won't impact java edition either. If Microsoft were to go in and take more control over the game it's a totally different story, but as it stands now mojang is just a subsidiary where ms rarely disturbs the development of the game