I find that many comments on this subject here don’t seem to consider that a majority (perhaps a large majority) of citizens in their nation support these policies

Because they don't understand the technology or the consequences.

When they do, they will change their mind (and probably protest loudly that they never wanted it in the first place).

See Brexit for a clear example.

But the argument I see is that the politicians are acting tyrannically against the desire of the voters.

some voters. The voters who actually understand the technology and the consequences

That's why democracy shouldn't be worshipped as the end-all be-all key to good government or good society. Or as Churchill put it, democracy is the worst form of government, except for all the others.

Freedom and liberty should be the foundations of a healthy society. Democracy should be reserved only for those things that must be decided collectively and universally enforced.

What kids do on their phones doesn't even come close. Let parents and vendors decide what their kids and customers can do. I've met plenty of well-adjusted kids who aren't on social media because their parents don't let them.