What you're missing is that it is enough for one single law to be problematic. If we had a complete, utopian set of amazing laws that provide happiness to all,

What you're missing is that it is enough for one single law to be problematic. If we had a complete, utopian set of amazing laws that provide happiness to all, and I add just one law : "All citizens have to agree with every edict, statement or choice of SiempreViernes. Expressing disagreement or doubt is a crime, punishable by exile, lynching or lifetime imprisonment." All of a sudden this society just became a nightmare. Yes the majority of people can probably still live an OK life, but that single law has a gigantic downstream effect on happiness, stress levels of all, and life expectancy of free thinkers. Now add the idea that you're able to perfectly prevent crime, and you now have a totalitarian surveillance panopticon in place to prevent me from even writing any doubts into my personal journal.