Does anybody really know anything which goes on under the hood, all the way down to transistors? I think it is half a century since this was even possible for a single person.
but there is a difference between knowing vaguely how internal combustion engine works versus treating your car as a magic box from the future. (which of course now most cars are, you can not even disable the tire pressure alert after you pump your tires without going to the service shop)
I fear that nobody will even teach the fetch-execute cycle to our kids.
I follow the rule of thumb that you should understand the layer you are working at, and one layer below. Understanding all they layers is great, but will take you a lifetime.