Seat belt warnings became mandatory in the USA in 1972[0]. From the mid 1970s until fairly recently, the warning tone would stop after a few seconds.

[0] https://www.nationalacademies.org/read/10832/chapter/5

I've known people who would just endure the warning noise until it stopped.

Many of them are just a light, and that's it. Or maybe the buzzer was burnt out lol.

My parents disabled a couple by pulling a fuse or cutting a wire, but a lot of their use of the vehicles was off road at walking speeds. They wore seat belts on the road.

I've had annoying seatbelt warnings on my cars aging back to at least the 90s.