I am well aware that my assumptions are probably wrong
No, no, this is entirely accurate. It’s just that the Linux-a-boos would love to tell you otherwise. But it’s all a bunch of circle jerking. The people who are willing to deal with that and have already dived need justification and will tell you it’s simple.
Sure, some distros are a bit more hands off and “works out of the box”. But you still have to find the box. And figure out how to open the box. And figure out how to get it out of the box. And then it just works. Until it doesn’t.
It’s not as hard as it used to be, but anyone telling you “any normie can just do it and never look back” is full of shit. It still has its hurdles and you’ll still be occasionally troubleshooting your own PC. Most people don’t want that. But the people who do are already running Linux.