So how real is the risk of burn in on an OLED screen?
I have not experienced burn in. My OLED has not shown burn in. At first I was really careful. However now I don't really think about it.
My son has had a 65" LG OLED, for longer than I have. He has had zero burn in as well.
So my hunch is that in sensible normal use the risk must be zero or close. I suspect that you would have to be a total idiot and leave the same screen on the same image for a week! I would not put this into your purchase considerations.
I would say once more, that if wide viewing angle is a must for you, then an OLED is your only option. However, that is not bad, as OLED is far superior to LED in everyway. I can honestly say, I have never seen a LED TV that I like. The only TVs comparable are plasma, but they are no longer available. Our other two screens are Panasonic plasmas, a 65" and a 55". Both have very natural colors, but the OLED does best them on detail, as long as the source is a good 4K source. I can tell you that sources are not equal by a long shot. The plasmas emit significant heat, the OLED runs cool.
My beef with LED TVs is their over vivid colors, with their inability to produce those natural pastel shades. Plasmas and OLEDs do this well.
In my view the LG OLEDs are the best currently available with Sony a close second. However I think on my evaluation LG wins by a nose, but that I can not be certain of. So I suspect you would be happy with either.
I should also say for the record, that my next door neighbors also have two LG OLED screens, one for about a year, and the other for about a couple of months in their basement. They have had zero issues.
Anyone can be unlucky with any purchase. However that is a pretty good record. My son did have a stuck pixel early on, and LG replaced the actual screen under warranty, with the repair being done in the home. This happened early in use for what that is worth.