Edit:
Obviously this CAN be fixed. But only by Plex updating their meta.plex.tv server, as this is where the ratings come from. No need for endless debugging your setup guys!
Also, RottenTomatoes ratings share the same issue, in case anyone are considering changing to that, to solve the issue. So, not a workaround.
And, plugin / agent support is no longer. In case anyone considered something like the excellent OMDB plugin as a workaround:
@trumpy81 As mentioned in another post, this is not about all ratings missing. The issue is that many (most?) ratings are either wildly inaccurate / outdated - or missing entirely.