I don't recognise the 5g battery life issues personally. I do 100% agree the GPS thing is such a bad decision. It just becomes noise that no one pays attention to anymore.

I ended up using my public ip address in combination with a list of known ips for home and work and such, and building my HA automations around that. I wanted to do it with wifi SSID's, but that also requires the location permission and triggers the indicator (which is understandable, just wish I could still read SSID's with location services disabled entirely) (or, just let me disable the gps antenna and leave everything else).

It certainly could be something else other than 5g but it's one of the first things that gets thrown around when battery drain is mentioned and the mobile internet was the main user of power on the phone.