iPhone asks to trust computer each time when tethering hotspot is on
In the past when the trust store became corrupt, I would see this. Have you followed the reset location process listed by Apple?


https://support.apple.com/en-us/HT202778


Once you do that, I would connect the phone without tethering enabled to just get a plain connect and make sure the computer and device are copacetic with reconnects that don’t prompt.

Once you’re past that, then try the tethering again.