If you don’t want to use the genres suggested by Roon, then you can tell Roon to just use the genres in your files’ metadata - Settings > Library > Import Settings > and set “Use genres from Roon’s metadata database” to “No”. Click “Save”, and the settings will be applied.
Depending on the size of your library, this may take a little while. You can see the progress indicator (a spinning arc) in the top right of your Roon screen, next to the Bookmark icon. Click on the indicator, and you’ll see a progress bar displayed.
Thats what I do as indicated by the above comment.
Other people reported the issue which is unique to v1.8.
What happens is Roon, even when telling it to use the genre in my files creates phantom genres.
Which is to say, genres when no albums. I got crap like reggae, country, childern genres with no albums.
My files 100% only contain one of three genres (blues, jazz,rock) so having these phantom genres is not helpful (which is not what I really want to say but will keep it at that).
I have previously reported this as an issue (as did other people) including screen dumps showing roon metrics that indicated my albums were only in the three genres listed above plus the crap phantom ones.