> They use the words WiFi (or, as we say in Germany, WLAN) and "Internet" almost interchangeably.

I was helping our neighbor with WiFi issues. They asked at some point if a "WLAN-Kabel" would solve the issue :)

The sad part is that they realized the mistake a minute later, and since I didn't say anything but just answered the question (I understood what they meant, no point correcting the technicality), they assumed that I was just laughing at them behind their back / internally. Turns out once again that tech is as much social as it is technical, and I really struggle with people who think everyone else is hiding something (they vote accordingly, let's say)

That is true everywhere. I think operating systems could do a better job at informing about the health of the internet connection in words the user understands. What seems to be the current bottleneck:

Your router does not respond. Turn it off and on.

This comes close: https://www.getapp.com/all-software/a/breakdown/

You can’t blame them, though. I live in the industry for over 25 years now, and when 5 Ghz wifi got introduced, and started to live alongside 2.4 Ghz with all the different protocols, I was like: "Nah. Screw it." I honestly have no idea what the current hot stuff in terms of wifi is.^^