Ya, burn in isn’t as big an issue now. For TVs what’s more likely is if you only watch movies with bars on the top/bottom due to aspect ratios that you might not use up the OLEDs there and they start wearing out at a different speed than the content. Then you start seeing bars watching full screen content.

But it’s not actual burn in, you would just need to play something special that hits those areas and not the center to even it out.

It’d take quite a long time to cause this though.