My understanding is that Davis quit drawing the strip pretty early on and has other people drawing it ever since.
Something I think a lot of people don't realize is that Japan has a much healthier media ecosystem in many respects. Like we just don't get new comic strips here and haven't in decades whereas in Japan they get new 4-koma like Bocci the Rock and The Demon Girl Next Door all the time and these get anime and video games and merchandise and make tons of money.
Our media industry has to realize that it doesn't just have a cyclical problem but that it is stuck recycling the same old properties over and over again as it shrinks. It's got to give a chance to some new blood.