> I often get the feeling that in these circumstances people derive first principles from specific desired outcomes.

But that's exactly how laws are made. E.g. why do we have consumer protection? Because it helps us! It's democracy in action.

It's not like nobody would ever build another forum if there were laws like the ones proposed by GP.

And if you're worried that every little forum should comply to complicated laws: we could make it so that the laws only apply to large players, e.g. >1M users.