[theamk]

I don't think "no one" will even happen - nor with potato, nor with mechanical skills. There are books which tell how to do all sort of things, starting from the refining metal from ores, and there are people reading them. I have no doubt that minute details will be forgotten, but they were discovered once and could be discovered again if needed.

Yes, horses were replaced, but go outside of city and there are many horse farms, and some of them offer horse riding classes to general public. Should something happen to the cars, the knowledge will come back. Same way, even if an average JS programmer has no idea what "differential pair" stands for, there are plenty of people who _know_ what this is, and can at least read the eye diagram.