To clarify, the PC is running GNOME with NetworkManager. I'm sure NetworkManager is responsible for the "just works" part.

This saved me many times when I had a WiFi adapter that required installing broadcom-wl in order to work.

Yes. Doing this on iOS is... an adventure. I don't remember the exact steps involved, I never had to do this myself but my friend did, but as far as I know, you had to somehow download the Itunes installer with your iphone, trick it into thinking that it's a photo, transfer it to the computer via MTP and then turn the photo / photos back into an installer.

If Android is connected to a 4g mobile network, it works too.

With my previous Samsung, I had to reenable the tether after every disconnect of the USB cable, which was every now and then. 😕 My current phone is able to do wifi hotspot while having a wifi uplink as well so I don't have any motivation to use any other way to tether other stuff to the phone.