I don’t know if the problem was ever fixed when the resolution weirdness showed up again in Dec of 2018. It was mentioned in a couple of threads, but drew little attention. Here’s one:
When the problem was the reverse in the thread @JuiceWSA mentioned , it affected how the Roku (and only the Roku, as far as I know) and the server determined how a file was played, and the false 576p resolution forced a transcode to one of my users who had a slow connection and had quality set to 1.5Mbps, 480p despite the fact the bitrate was well below the setting. For the Roku, the reported resolution was also one of the factors considered.
I imagine, that even if a Plex employee or Ninja notices this thread, they will tell you it is purely cosmetic, as they did before. Even though that was not the case. 
