Can any system of laws turn all human effort to tasks that run a surplus? Constrain us to market activities with producer and consumer surplus, and non-market activities that people enjoy, or at least tolerate?
Yeah, of course they can. That's the whole point of law.
Don't get me wrong, they can't eliminate risk. But you might choose to meet a new person, even if there's a 5% chance they're a jerk, because on balance you're coming out ahead, maybe with a new friend. That type of risk is actually really useful and itself pro-social – if we only picked up the surpluses we could grab risklessly, we'd only get maybe a couple percent of all the good out there. Most things could go wrong – most of the time, very slightly. That's good.
This is why I'm so optimistic about immigration. Aside from all the concerns about police reform, and the seriously strange and crumbling state of American society, I'm optimistic that the American legal system can make all human endeavors either generate surplus, be neutral, or be outlawed/regulated to maintain that surplus. As much dysfunction as there is, we're actually pretty good at this, and many, many countries are not.
Don't get me wrong, many countries can limit activities to those producing surplus – Canada does that great. But they don't have a sense that the gates are basically open aside from that – they don't get all the surplus they could. It doesn't even seem to be one of their goals. When Americans talk about freedom, this is something close to the center of that, even if they'd never describe it or imagine it this way.
Note, I'm not saying people should benefit from everything we do. I'm saying that all people, together, benefit more than it costs them. That doing the activity makes the whole system better. This is the classic case for how markets should be designed – once you have enough rules for that, you want to scale up the volume. Limit it as little as possible, so long as everything allowed in net-positive-sum. It's possible Canada even does a better job than America at this, despite not appearing to have the same sense of caution. Occupational and business licensing are, in many ways, an anchor tied around America's neck, and that's just the most obvious field of nonsense. But I'm optimistic about America improving, where other countries might not, over time. They try to work backwards from consequences, and the hidden effects of those rules are where all the costs come from, making them near-impossible to analyze counter-factually. But if you reason forward from principles, and require evidence of harm before you do anything and make persistence of a rule dependent on whether the harm would return, then perhaps, you have a solid chance at helping people help each other as much as possible.
Of course, you'd have to want to do that, and America's not there right now. They're in a really big fight over how good a person a reality show star is. They're busy. But when they're ready, they might be persuaded.