I have a colleague who has an OLED screen since 2016 and wouldn't buy an OLED since the manufacturers imply that it is natural that the burn-ins and retentions happen and because of this they have developed and implemented a series of mechanisms to minimize it, he says.1) It's common enough but 2) it's not endemic.
He is so obsessed with the issue to the point he recently cancelled his Disney+ subscription because they decided in a new show to put a logo in the bottom right of the screen.
He didn't dare to use megadrive-mini or snes-mini for fear of burns (because when he was younger he saw the famous retroprojection TVs with retentions and burns evident in a store that had the Turbografx connected to one of those TVs).
He bought the TV for the new consoles, but there are many games that have fixed stuff on the screen and he told me that this may him rethink whether to buy another OLED or not.
His OLED is working fine though but he takes every measure to protect it.