I think you don't distinguish enough between professionals and capables.
All your points are either "sysadmin" or "complete buffoon" and nothing in between. That's not how reality works.
You absolutely are expected to be able to check your oil and just a few years ago, you were expected to be able to change your tires. That doesn't make you a car mechanic, but a capable user.
I'm absolutely not a car guy, but I know how to change a tire. Why? Because it's necessary knowledge. I also know how to file my taxes, even though I'm not an accountant or tax consultant. Again, because it's necessary.
No, but it causes alpha particles to be emitted.