So I have wondered about this, but it doesn't explain why the battery life would be better — unless the idea is that they're losing money on the devices by using advanced batteries because they want to track you.

Regardless, I don't give the Amazfit (Zepp) app access to my location, and the watch itself doesn't have wifi connectivity. I suppose they can see my IP address when the app phones home, but I don't really care that the company knows my approximate location.

??

GPS uses very little battery.

That's a strange assertion. Devices use WiFi positioning whenever possible to avoid using GPS. Do you have some reason for saying that?

WiFi position also uses very little battery. And are you under the misconception that offbrand watches don't have location functions?