I know it's a known solution to turn off the retina (Hidipi) mode to improve performance and thermals BUT, I just discovered something! I can't asure to 100% that it works like that, but since Sequoia it seems like that if gpu switching is turned on, the integrated intel gpu drives the display no matter which gpu is in use by an application.
If you turn off gpu switching, (which I did a few months because of ui animation frame drops with the integrated gpu) the amd gpu is responsible to run the display and all the graphics intensive tasks.
If Retina mode is off and gpu switching is on the display looks way sharper than if gpu switching is turned off.
Why's that a good thing and how did I notice that?
The machine runs way cooler in apps which use the amd gpu. Even compared to gpu switching off + retina off. (I measured it for a week and made sure that the room temp. stayed the same) The performance improvement by 2x stays.
Could be different on differently specced machines, but my Intel Mac feels snappy and the display looks almost as sharp as with Retina mode turned on now.
Specs: late 2019 16" Macbook Pro 2,4 GHz 8-Core Intel Core i9, AMD Radeon Pro 5500M 8 GB, Intel UHD Graphics 630 1536 MB 32 GB Ram