While in practice I do this since Symbian times and never had a problem with any battery whatsoever.
The theory is sound that there might be a degradation, but I doubt it’s dramatic.
slow fp3: there were some interaction patches in 0.18, I wonder why they do not continue to make a difference. Those were boost settings, that clock the cpu higher while one interacts with settings or predefined apps. How can one benchmark fluidity and compare across versions?
battery fp3: I was debugging battery usage on the fp3 and moto devices not long ago. 1% draw per hour during doze can be ok, more I would see is a bug - 0,5% is ideal. There are some issues in the backlog on battery drain with some debug help if someone has 2% draw during doze
is it not possible to optimize the kernel?
I know that on XDA, there are kernels optimized for phones with the same base as the fp3+
I’m also having same problem of a very slow feeling FP3+, only had for a year and 3 months but then my 5/6 year old iPhone actually feels snappier! Lags on UI interface even on highest performance battery mode. I’m considering getting a regular Fairphone 4
For the ui I may have a little hint.
In the developers options is a possibility to decrease the animation time.
I set the values to 0.5. See the picture. Test what value suited you.
Just now I set every value to off.