Games with static content, sports, etc. have not really exhibited any negative effects after over 5,000 hours. It was really only the CNN use cases.
Also, from the RTINGS.com test:
This test alone only demonstrates the effect of one of the use cases described above. It does not show the effect of changing between multiple sources (such as watching football 20% of the time, playing high-risk video games 50% of the time, and playing low risk video games 30% of the time)
Mixing content and using the panel normally could prevent any such issues although I do think that some panels may be more susceptible than others (e.g. panel lottery).
I owned a plasma for around 5-6 years and bought a new LG OLED E7 back in 2017. I have never had burn in on the plasma and after over a year of ownership I have not had a single problem with my LG OLED either. No image retention or burn in.
I play the majority of my games on PC with a monitor whenever possible but I do still play a fair amount of console exclusives on my TV. I have played hundreds of hours of games with static content like Xenoblade (100+ hours), Xenoblade Chronicles (approaching 100+ hours) and Persona 5 (60+ hours) and watched several hours of Twitch streams with static content on a daily basis like Overwatch and Overwatch League. During the first season of OWL, I watched nearly every single game which was roughly 4-6 hours a night for 3 or more days a week. I still watch some streamers on a fairly regular basis like Seagull, Dafran, XQC, etc.
I might not play any games on my TV at all during the week and then binge for 10-20+ hours of the same game(s) on the weekend. I might also play 10-20+ hours of the same game in one week but spread out in 2-3 hour gaming sessions mixed with a lot of other content. While I am not overly concerned about burn in, I would certainly avoid playing the same game with a static UI for hundreds of hours with no other content mixed in.
I am willing to accept the risk (which based on the tests from RTINGS are extremely minimal) for having the best possible image quality.