The problem exists in that, if there is a ban hammer, it gets used.
And suddenly, you are now in danger of losing everything you built.
Such is happening on ThemTube right now.
What starts off as "noble", "getting rid of the bad guys", turns into getting rid of people you don't agree with.
Thus, if the ban hammer exists, then honest person feels the sword of Damocles hanging over them, and the dishonest person just knows that hey, at some point i will get caught, then you just start another.