> Like all the other monopolies that governments already have

Your examples are things that aren't inherently monopolies and are significantly worse if you try to make them such. It's better to give people the right to self-defense than to put them in jail for violating a "public security" monopoly for not allowing someone else to kill them when there were no police around. It's cruel to prohibit someone from paying for their own healthcare in cases when the procedure exists but the public system won't spend the money. What argument could you even make for prohibiting private inspections of products and services the likes of Consumer Reports?

The things that are better as a monopoly are so rare that they plausibly don't exist.