The first ‘Main albums’ displays the albums that are present in your library (physically on your server or added from Tidal using the ‘Add to library’ button).
The second ‘Main albums’ has a little Tidal logo in front of it. It shows all ‘main’ albums that are available in Tidal, but not added to your Library.
Can’t we have an option to see ALL the albums of an certain artist/band in ONE VIEW regardless if it is in my library, Tidal or that just exist via metadata (ie. not in Tidal due to licensing etc) ?
The distinction on the page is only made for Tidal albums that have not been added to the Roon library.
Once added these albums will be displayed seamlessly with the locally stored albums.
Do you have a Tidal subscription? If so try it out and you soon get a feel for how it works.
EDIT:
Just re-read your post, and I think I have misinterpreted it … so ignore the above.
You could put your request in the Feature Request section of the forum, Roon will then see how much traction is gathers.