And yeah, I've experienced image retention on non-OLED screens. the LG-made 2560x1440 IPS panels that used to get used in 27" iMacs would after a few years start exhibiting image retention, though it'd at least fade if the static elements that sat long enough to cause retention were hidden. I think this was caused by the heat generated by the computer part of the iMac though, because the Apple Thunderbolt Display that used the same panels never develop the issue even after a decade+ of usage. I also haven't seen it happen on any other IPS panels I've owned.
You'd think modern desktop OSes would allow subtle shifting of persistent UI elements by a few pixels to avoid burn-in. LineageOS already does this
If you want to rotate the task bar or dock or menu bar around all four edges of the display every day then maybe, but that'll be hell on your habits and muscle memory.
I think for normal TV usage it is a non issue. The only times I have heard it being a problem is when someone leaves their TV on for a week for their cat or something.
My oldest OLED TV will turn 6 in August and has exhibited no burn-in.
I think it ultimately comes down to what you're watching. You're likely to experience burn-in if you watch something with a persistent banner like 24 hour news.
For example, my 2 year old LED VA Panel monitor already has burn-in where the task bar is displayed.