If you could replicate that would be very interesting since a single datapoint doesn't say much.

Brand new oneplus 8T and I was getting ~1 day of battery life with about 3-4 hours of use. I never enabled any google services and that was the default configuration.

I went app permissions and disabled everything that I was able to disable. The only apps that had default permissions always enabled were google services. The battery day is now ~2 days with slightly heavier use and the display running at 120Hz instead of the default 60Hz.