My feeling is that the coulomb counting on the Pixel 8 Pro is just not very accurate, so the phone thinks it's at 80%, but is really at 60% or 40%.

I still use the feature, but now I have to top up during the day every so often. I suppose rationally I should just charge to 100% rather than take a medicine that causes the same side effect as the disease its meant to treat, but I'm not that rational.