Users should have the power to defederate in addition to admins.

They do.

Not everyone wants the same thing or has the same idea of what constitutes ‘harmful’ instances.

That’s why I didn’t say “everyone”. I said “people who join those instances”. If you don’t want that, you can choose our migrate to a different one. Or even create your own.

Yes, this is why it’s important to take individual control away from the user; to push an agenda.

You’re correct, of course, but “agendas” are not inherently negative.