I think it’s against electrical code. You can have a pull string because the wires are on the ceiling which carries the same risk of getting water in it as the light itself that is also on the ceiling. A wall switch would be lower on the wall and has the risk of wet handed people coming directly in contact with it
Sometimes you’ll see those “shavers only” sockets in bathrooms, which are different from your typical wall outlets in that they have a GCFI (also called RCD), and/or a built in fuse to limit current, and have a floating ground.
The light switch and light is likely tied to a “live loop” system which runs 230V, and has a 5 or 6 amp non-GCFI breaker on it. That is considerably more dangerous for a wet human to come in contact with.