This has very little to do with Chromebooks. It's happening in countries where they are rare as well. The main cause is the fact that things for the most part just... work now. The experience on PCs and especially smartphones has become so streamlined that it doesn't require that much knowledge to be able to use them at a sufficient level. Plus smartphones have become the default device for most people so they almost never have to interact with stuff like the file system or anything complex. Most people don't care about understanding how computers work more than what they need them for, and that's fine.