I have jellyfin with the radarr/sonarr/prowlarr combo going. I can “heart” things in jellyfin. But it’s recommendations are only things I already have downloaded. I see discovery in radarr, but no way to tell it if the movies I downloaded were good or bad. So I must be missing something.
You can use jellyseerr. I have been using a lot the "coming movies/series " section, once installed. AFAIK, doesn’t have it’s own algorithm, and relies on tmdb trends. But it can be integrated with *arrs , so usually I prefer to spent there 5 minutes and made all my requests to sonarr and radarr. Also, has docker implementation, if it can be useful for you.