Another big problem is that designers never got the "semantic" bit. I don't know how much of that is that most designers aren't used to thinking systematically

Another big problem is that designers never got the "semantic" bit. I don't know how much of that is that most designers aren't used to thinking systematically and like to design a page at a time instead of a system for a whole site and how much of it is CSS being structurally wrong. So we have MUI and bootstrap to impose an application-like structure or tailwind to just "do what I mean".