Burn in is far from the only issue, we mostly cracked how to deal with burn-in back when we had to use CRTs as monitors(Quick to active animated screensavers and pop up taskbars more or less solves the issue), they could burn in a fair bit worse than modern OLEDs, but standards & expectations are different nowadays(Could you imagine trying to RMA a 50kg monitor and getting told postage costs are on you?).