Prohibition of alcohol wasn't a problem because mitigating social issues caused by its abuse is a bad idea. Prohibition was a problem because it was a bad tool for the job; it didn't solve the issues it was meant to, and caused many more of its own.
Drugs, pornography, prostitution and violent video games aren't the problem (except for people who don't think much). Drug abuse-related crime and health issues are the problem. Sexual abuse and crimes are the problem. Human trafficking and forcing people into sex work are the problem. Violence is the problem. I agree that bans are a wrong idea, but I also disagree about the role of the government. It's absolutely a responsibility of governments to deal with these issues - because really, no one else can.
> Government is force, no matter what, and even democracy is tyranny of a thin majority.
If democracy is a tyranny, then so is the "free" market. A tyranny of those who have more, who rule over those who have less. The tyranny of the economy that forces most people to make bad choice after bad choice, because the alternative is starvation. Truth is, there is no absolute freedom to find anywhere. Not in a world with so many people, not when the "minimum viable reproductive unit" of human species is a village. It's a game of finding the balance that ensures most freedom and most happiness.
Gambling does not violate consent. Drug usage does not violate consent. Prostitution does not violate consent, or in the cases that do, those independent instances are where enforcement needs to occur.
Is this a matter of competence or a matter of principle?
If I can talk to some people and without threats or deceit convince a good number of them to hand me over all their savings (using a zeroday in wetware for example), does the government has a right / responsibility to stop me?
I expect ad-tech and other persuasion techniques will only become more effective. At what point do we declare regular people unable to consent similar to the way we say children and few other groups can't legally consent?
In my opinion, governments overreach is when governments starts to control the population's choices (e.g. prohibition or ban of illegal & experimental drugs). Government influencing the population's choices (guiding them towards "good" choices, e.g. by limiting gambling, taxing alcohol, enforcing true labels on food) can be a very good thing, [edit:] especially in situations when humans tend to behave irrationally (i.e. because our psychology / evolutionary mechanisms are hijacked).
But the illusory nature of "good" isn't even the primary problem. The real problem is tyranny. Government is force, no matter what, and even democracy is tyranny of a thin majority. Unless the powers of the state are limited in terms of its objective capabilities, then what is subjectively being enforced by its authoritative capacity is necessarily tyrannical to the minority.