Right, surveillance needs to go both ways. The watchers need to be watched.

Bingo, like most political problems it boils down to human nature.

> The problem of surveillance isn't a problem at all if you could trust every actor to do things right, it's just that you can't.

I disagree. The problem of surveillance still stands even if you trust each and every single actor directly or indirectly involved in it. The critical aspect is that surveillance is made possible through significant investments in infrastructure, and infrastructure outlives actors and governments and regimes. Once you have the infrastructure in place, all it takes is a bad actor to weaponized it and use it to oppress and control you.

Your argument is contradictory. If you trust 'each and every actor directly or indirectly involved in it' then by definition there can be no bad actor in the future to oppress you.

My point is that actors can and do change over time.

Just because you trust who is in charge today that does not mean that said person/organization will continue indefinitely as-is.