A seatbelt wearing is very similar to sitting in a the seat of a car. Using ropes is very different from no ropes. Rope failure is probably more common than seatbelt failure so the safety margin difference may not be as great.

If your rope fails while climbing, it’s almost always user error (using the wrong gear, using damaged gear, risky placements, etc).

What about having airbags? or driving a bigger car than everyone else? or not driving faster than 15, 30, 55, 70? Or not driving at night? Or in the rain or snow?

I always wear a setbelt and when I climbed was roped in, but to claim these generally acceptable risk mitigation techniques aren't subjective is just claiming your beliefs are everyone's beliefs. That's not true.