My PC doesn't connect to my Fairphone 5

[AnotherElk]

@CraigHB

For use with Windows, the “MTP” driver required by ADB is built-in, no user action is required other than plugging in the phone.

Could be kind of rare in the wild, I guess, but there are official Windows versions out there without the Media Player components necessary for MTP, called Windows N.

@AnotherElk

Just as a reference … If there would have been a problem with MTP from the start, it could have been due to a Windows N version. (“N” = without Media Player, result of an old antitrust case)
A Windows N version would need the “Media Feature Pack” before it can do MTP. This should be installable via Settings - Apps - Apps & Features - Optional features (or something like that, German locale here) in current Windows 10 N, for older Windows N versions there were dedicated downloads … Media Feature Pack list for Windows N editions - Microsoft Support