Our laws only work because of a hidden assumption that trivial or victimless crimes won't be prosecuted. This assumption isn't always upheld, but automatic surveilance would break it pretty much every time.

Even if our laws were actually written with perfect enforcement in mind, only outlawing what's actually antisocial, I don't think I could ever trust a government enough to give it that kind of power. Mass surveillance makes it easier to enforce any law, just or not, and most countries haven't been able to go even one lifetime without turning into a totalitarian hellhole or at least persecuting part of their population.

Another part of it may be that emigrating is so costly (not just in money) that most people won't ever be able to do it. When you're de facto forced to live in a country whose laws you (partly) disagree with, it's easier to add barriers to law enforcement than to get those laws changed.