[int_19h]

The older UIs had those concepts, but it wasn't stuff like "how DNS operates". It was stuff like, "every app that works with documents has a File menu with New, Open, and Save in it". Or, say, "if you want to see all available actions for something that's represented by an icon, right-click for context menu". I taught my mom like that, and she was amazingly productive at learning new apps. She didn't always find the most efficient way to do something, but she always found a way to do whatever she needed to do.

Modern UI ditched all that. Just about the only consistent element is the hamburger menu, and how it looks once you open it varies drastically from app to app. In many cases, it's hard to even tell which elements are active and which aren't (because everything is flat!), and if they're active, what exactly they will do if you try to interact with them. When I got her an iPad - the very first one - she really struggled figuring it out, because not only all the existing concepts didn't apply, but there was no rhyme or reason to it in general.