Three points.

First, some laws probably don't have any positive impact.

Second, there's a difference between accurately summarizing trial results and extrapolating that to the impact of a new law. If there was a death penalty for not wearing masks, perhaps compliance would be better than in the trials and an effect would be shown. This doesn't mean that the trial analysis is wrong, you just can't draw a conclusion about the law from the trial data.

Third, laws have multiple purposes including Justice and Punishment. Some murderers might have zero chance of re-offending but we still want to punish them as a matter of Justice, not because it makes Society safer.

That is why we have police officers to try to stop the people who have proven they are willing to murder.

Do you want to be the person going around policing mask wearing?

Well depends on who you ask.

I generally think laws should be codifications of societal norms. Which also implies that as societal norms change so should laws.

So even things such as murder which people do and we don't want should be codified as illegal. But even if nobody committed murder anymore it should still be illegal as its against societal norms.

Presumably less people kill in that case.

Would you kill of that would be legal?

If I did decide to, and it was your spouse/child/parent/sibling, would you then kill me in revenge?

Maybe this is a ridiculous metaphor since public health is not what the justice system is trying to accomplish by imprisoning murderers.

Point was that some questions are not about law. Im sure you are not going on red just because you could get fined for it.

But also, you'll be fine to go on red in the middle of night, where noone is around. Personal responsibility is unfortunately removed by centralised regulations and laws. Thats the problem.

In reality things are complicated and one principle[1] cannot account for all situations, so we deal with things differently as they come up. Murder happens to be an extremely old problem; public health is also, but knowledge of microbes and infection mechanisms are brand new, so we are still figuring it out.

[1] "personal responsibility" makes little sense as a moral catch-all when ignoring your own health can cause other people problems

- ...ignoring your own health can cause other people problems"

How much of Netflix cause health problem for you? What about food? How much of junk food are you eating? Or maybe we should ban tabaco and alcohol. Or profesional sport. All of that is potential threat for your health. Being overprotective could damage your mental health... etc.

More regulations = less personal responsibilty.

Your comparisons between issues in modern cultural and political concepts are fascinating. Please tell me how overeating, obesity, personal addictions, competitive athletics and media consumption are related to microbial infection vectors so that I can write a definitive thesis about externalities and how they don't exist because I want to live in a libertarian fantasy world.

I will make a comparison, tell me how you find it: "Dumping waste into the river shouldn't be illegal because you dump your waste in your toilet every day and it goes to the river."

Does it sound reasonable? Sure. But I haven't defined scope and I haven't defined effect and I haven't even defined what 'waste' is; I just made up two scenarios which could have similar outcomes and then called it day -- but if you actually care about what happens to the world you need to get a little more detailed than writing silly grandiose political statements and making non-sensical metaphors comparing indicting someone for murder with crafting public health policy.

I'm just reply to your statements with questions and you refuse to answer by creating new conclusions.

I don't see any questions except the murder one (which I noted is non-sensical) and some rhetorical ones.