For me, there are two big features that make Roon great.
First is all the written/photo content. Yes, it's available elsewhere, but in Roon it is part of the interface, so my browsing for music and my learning about music are thoroughly intertwined.
Second is that I can find things like cover versions and collaborations between artists with remarkable ease. One day I decided to find all the albums where Ron Carter and Tony Williams were in the rhythm section together. It took seconds. Another time I was able to verify that two Nashville musicians I like, each of whom seems to collaborate with everyone in the known universe, had somehow never worked together.
That kind of granularity in filtering search results is just crrrrazy, and it's really easy to access. And if your "collection" is the same as Qobuz's or Tidal's collection, you are essentially searching the whole world of music for your answers, and not just the stuff on your local hard drive. (I still harbor delusional fantasies that someday they will have access to an API that lets them integrate Apple Music, which has the best catalog I've found.)
I should note that we're here on an audio website, and neither of the features I care the most about are audio-related features. I actually do use the parametric EQ feature on headphones and other audio zones with suspect frequency responses, but it's not any sort of game-changer for me. But there are people who really love the bit-perfect audio and signal chain overview, and all that other audio nerd stuff. I think if these are the things that matter to you, there might be a product that works for you, but cheaper. 'Cause Roon ain't cheap.
But I spent $700 on a lifetime membership as soon as I installed the trial version and saw some of what it could do, and it brings far more joy to my daily listening than if I had spent that $700 on equipment.
