Even basic users need to do things outside of a browser. How do you upload pictures from your phone to a Linux desktop?

You plug in your phone, indicate file transfer is ok (on your phone itself, which I assume must be the same for windows) and nautilus gives you the option to browse it.

nautilus, nemo, etc support MTP and have done so for many years. You just plug your phone in and navigate to it in your file manager, which is the same thing you'd do on Windows.