Seat belts work. Use them. Those won't don't use decimate themselves over time. E.g in Austria of the 178 car occupants killed last year 42 didn't wear a seat belt[0]. Those 23% is far above the 8% that did not use a seat belt in observations[1]. Numbers for other countries are similar or worse.
[0] https://www.bmi.gv.at/202/Verkehrsangelegenheiten/unfallstat... [1] https://www.oeamtc.at/presse/oeamtc-erhebung-jeder-13-pkw-in...