I believe modern cell standards use either NAVSTAR or base station broadcasts to synchronize time slots, adjust beam forming parameters, arrange call tower handovers and such to provide Tokyo or New York or Delhi relevant density capability, and thus GPS functionality is a requirement, apart from convenience of whether it’s available to userland runs in application processor.
Virtual UART drivers for every phone since 3G HSDPA creates GPS NMEA ports on your PC and it spits it garbage when it feels like doing.
If the modem is on, the carrier can figure out your location relatively precisely from your transmissions, even if GPS were disabled.
So the real loss is that you can't use the device for navigation/mapping without turning on the modem.
Right?
At least this can be resolved by using an external receiver.