The good news about Denmark is that their unemployment rate is only very slightly higher than the USA’s and was lower in the recent past. The Danish economy as a whole does a good job of keeping people employed, and it also does a much better job than the American economy of delivering high living standards for the poor. But mandating high wages for fast food workers has more or less the impact you would expect — low levels of fast food employment.
The standard response to raising the minimum wage is always why not a million dollars and hour as if that’s under consideration. $20 is too hight. Much to high. That doesn’t mean that $0 is the correct answer.