The thing is, “unskilled” jobs have a huge worker pool. Just about anyone can do it. Perhaps not that well, but it doesn’t matter much how well you do it for most of these jobs. Take a cashier. At best you might be twice as effective as the “normal worker”. Then compare that to what people call “skilled jobs”. Say a civil engineer. Here, your “normal worker” straight up can’t do it without years of training, and failure costs lives. For this reason, “skilled jobs” have a tiny worker pool and of those, only a few are adequate. It’s only natural that these few would ask for and receive a much larger pay. That’s not to say that “unskilled workers” shouldn’t be paid a living wage, but in a capitalist world, they will always be paid less.