For new (to me) artists, for whom I have no albums in my library (either added from Qobuz or Tidal or because I’ve added local files), “Top Tracks” appears to be a list of “popular tracks” from that artist. The kind of list of “top tracks” you might see when inside a streaming media service’s ecosystem (Google Play, Spotify, etc). But, if I have a few albums from a given artist in my library, “Top Tracks” quickly becomes a numerical sort on my most played tracks, irregardless of whatever the database(s) say are that artist’s most popular/most played.
I find both things to be useful. I’d be quite happy to see “Top Tracks” split into two separate sections, and have a listing for both; “Most Popular” tracks, and “Most played (by me)” tracks. But the feature as it stands right now, changing from one to the other, isn’t optimal, IMO.