how are a few people on a specialist forum representative of the masses
If anything, it improves the chance of not seeing burn in - prosumers will be aware of the problems before hand, and will actively seek to mitigate the issues through preventative methods such as avoiding news channels; your average Joe may not
Burn in IS a problem, simply due to the nature of the technology. It's organic, and degrades, but at different rates - there isn't the same consistency you see with LEDs, for example, and so you can have 2 identically specced TVs running the same programmes, same settings etc, and one could get burn in, and other may not.
I've encountered burn in on most of my AMOLED devices: Nexus 6P, S7 Edge, S8 and Pixel 2 XL. My XS will likely get it too
On a phone, there's little you can do, but on a TV, I think you're less likely to see it, since you can avoid pretty much everything with static UIs. As someone who primarily plays video games on my TV, I'd definitely think twice about getting an OLED - I wouldn't want to drop >1K and run the RISK (not guaranteed!) of my TV becoming defective, especially since it isn't covered by LG under warranty.
I think ultimately I would end up getting one, because of the horrendous inconsistency of backlight clouding on LCDs and superior contrast ratio of OLED