IIRC MAME reads the Computer hardware at the poll rate, adds it up until the driver's (not screen) vertical refresh rate. Can't remember how it handles hardware that asks for data quicker then the vertical refresh rate. But I saw a video of real gameplay and yeah, there is definitely ...
Does anyone know if there's a way to set mousepoll per application? I can't unload the usbhid module as I guess other stuff is using it so have to reboot. edit: in addition, proton 3.7 does not have this issue so it's fairly recent. I didn't try every version between that one...