We can't make batteries last forever, but we can help them last longer. Charging optimization is one Android 15 feature worth exploring, as it's designed to do just that.
Charging optimization in Android 15 explained
https://www.androidpolice.com/android-15-charging-optimization-guide/
I'd say its a worthwhile feature that users should actively enable imo
My Chromebook has charging optimisation, Adaptive Charging and Limit to 80%, and it works a treat stopping the charging when battery is at 80%
Especially useful if you have a device plugged in a lot