Personally I have not seen burn-in at Flight of Passage. I also have been told that they weren't OLED but instead expensive LCD displays behind tinted glass, giving the illusion of OLED which was still riskier in 2017. If there is in fact burn-in in the FoP pre-shows it could be because of the video pausing its loop overnight (and Disney techs not caring enough to properly shut it down, which wouldn't surprise me as Disney does not have a dedicated A/V team for their rides like Universal does).
OLED being at serious risk for burn in does not really apply anymore and you can treat a modern OLED the same as older display types. Mind you, static images and graphics on screens for extended periods have time have always had the potential for burn in dating back to CRT's. It's why screensavers were invented. It's why every gaming console since the mid 2000's, when LCD displays started popping up, have screen dimming features when idle. Consider the fact that most phones coming out now are OLED and they do not get burn in despite showing the same lock and home screen constantly.
The Tower of Terror pre-show would not cause burn in because no part of it is static. The still shot of Rod Serling, for example, is only a few seconds long and quickly refreshed with movement. Showing the same content over and over does not cause burn in, only static images on screen, for extended periods, consistently.
In similar vein, when solid state hard drives first started gaining traction, everyone was warned to not get them because they would fail easier and have a much shorter lifespan. But it's been over a decade and things have improved significantly. Today, solid state hard drives are the norm and you don't have to treat them any different than traditional hard drives.
Not trying to be condescending, just wanting everyone to get on board with OLED now that OLED displays are becoming affordable, so we can finally move on from ugly LCD screens and their bad black levels and bad viewing angles.