Several of the soundtracks in my local library have their Album Artist identified as Original Soundtrack/Original Movie Soundtrack/etc. rather than what is listed on the album cover.
Now I may be in a minority, and be one of the few people who still submit data to Last.fm, but as you can imagine…having the track artists submit as something other than the composer/performing artist does tend to mess up those statistics somewhat.
I suspect this is primarily an issue with some of Roon’s metadata sources (in my search for a solution to the issues, I know that AllMusic lists the Album Artist of The Greatest Showman soundtrack as Original Soundtrack, for example).
In general, I’ve had no issues with 99% of my library, but the handling of soundtracks is causing issues.