You seem very defensive in your position of advocating people be less safe on their bikes. Quite odd. Anyway, good day. "There is good evidence that bicycle helmets are effective in reducing head and facial injury in the event of a crash [...]" [0]
The evidence in favor of wearing a helmet while in a car is just as strong, but nobody is up here advocating for that.
By the way, helmets on bicyclists tend to make car drivers behave like even bigger jackholes than usual. https://psyarxiv.com/nxw2k "... public health research might be best served by shifting focus to risk elimination rather than harm mitigation."
The argument could be just as strong, but since very few people wear helmets in cars (only Formula 1 etc.), I think it's unlikely "the evidence" is just as strong; however, by all means provide us a reference.
0. Ivers R. Systematic reviews of bicycle helmet research. Inj Prev. 2007;13(3):190. doi:10.1136/ip.2007.015966 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2598379/