I’m not a fan of tradition for tradition’s sake. For me, if something can be improved I’m all for it.
My first exposure to dim sum was Man Fook Low restaurant. My parents used to take my brother and me there when we were children. It wasn’t specifically a dim sum restaurant, but they had some dim sum dishes. This would have been in the 1960s/1970s. I don’t think they had carts, but this was a long time ago and we all know how memory fades.