having vrchat running, go to discords registered games tab and turn the discord overlay off. then turn detection for vrchat off. then click the x thats next to the added games tab for vrchat to reset its detection settings. immediately turn the detection off again. this should remove it from the menu entirely (for the time being). doing any input in vrchat NOW may crash the game instantly. if not then relaunch the game and cause inputs.
it appears that the reason for this is due to discord trying to put the discord overlay on (the default settings as a result of clicking the x to reset its detection settings) but your user profile has the overlay saved to be off. i will tell discord about this bug but PLEASE forward this to them too.