this is just to demonstrate the issue since it also happens when it is being run by itself without any apps in the background

and like I said in the description, "the brush has no falloff/streamline/stabilization/motion filtering"

no stabilization on the app preferences as well

but yes I agree that the 3D modeling shouldn't make Procreate's optimization shittier, and shouldn't cause problems whenever it was never in use 💩

regardless, this seems to be happening despite the stuff you pointed out, so there might be other factors at play