I don’t know. I’d still practice caution tbh.
This one showed up on my Ebay search results just last week. It’s quite faint but definitely noticeable. The seller didn’t go into detail other than to list it as “Some screen burn. Reflected in price”
While I’m still pretty confident in apples oled implementation, I’m also very aware of the very nature of the technology. If apple were doing something that completely eradicated oled burn-in then I can almost guarantee tv/monitor manufacturers across the globe would be all over that. That kind of shift is literally monumental for the tech industry. A single handed game changer.
Enjoy these devices. They’re stunning but I for one will still practice caution and common sense where applicable.