A minimum-wage law is, in reality, a law that makes it illegal for an employer to hire a person with limited skills.
"Free markets" is a very general term. There are all sorts of problems that will emerge. Free markets work best when the transaction between two individuals affects only those individuals. Most often, a transaction between you and me affects a third party. That is the source of all problems for government. That is the source of all pollution problems, of the inequality problem. This reality ensures that the end of history will never come.
Reality ensures that the end of history will never come.