But where do you draw the line? Optional tempered glass? Optional seat belts? Optional ABS?
I think the idea is that some safety features are so important they shouldn't be optimal.
I think the idea is that some safety features are so important they shouldn't be optimal.
Not arguing against safety, and this doesn't relate to aircraft at all, but your examples are interesting.
Pretty sure all three of those were optional when they were new things. The pattern of being optional on luxury vehicles, then standard on luxury models / optional on normal models, and finally, standard on all vehicles...is common.