Sunrise is the sun rising over the horizon. It makes sense. Duh.
Not sure if you’re being serious or sarcastic-but the earth is rotating, so the sun isn’t rising over anything, duh.
Except the sun isn’t moving. Mechanical accuracy would be “horizon lower” or something like that. But that’s not as smooth. Just like “fossil fuels”, we know they aren’t fossils, we’ve known it for a long time. But it’s got better feel than “petroleum”. So the term sticks. Oh I just remembered another example: movie trailers. They got called that because they used to be after the movie, but they eventually realized nobody stays after for commercials and put them before the movie, but we still call them trailers.