I think most people with this particular need would prefer a portable hotspot, like the Netgear Nighthawk M5, but they are not cheap as you've found, any 5g and

I think most people with this particular need would prefer a portable hotspot, like the Netgear Nighthawk M5, but they are not cheap as you've found, any 5g android phone can be used in it's place, and so it probably a better alternative in many cases. Since you're talking about USB, and battery drain, you can probably assume that the phone will use roughly the extra power that is required to do the 5G data transmission and relay to the USB host, and so, if you connect your phone to your computer via USB, and enable internet sharing via USB, you've achieved USB dongle behaviour ?