Which is the same model as one of the other holdings of Muse Group, Ultimate Guitar. It has a wide database for user-created guitar tablatures for most popular songs. Starting from 10 or so years ago, the experience has deteriorated rapidly; they - push their "Pro" versions at the top of each search result, - overlay a bullshit video on the actual tablatures which is easily mistaken for a video tutorial for the song you are looking at, - user created GuitarPro tabs require an account to download, - there is an ever-present countdown until their 80% runs out, which resets every two days or so.
When I first heard of MuseScore and the fact that Tantacrul worked on it, I was quite excited about an open source notation app but I want nothing to do with it because of their parent company.
For many pieces of film/game/pop music, you can't even find a place to buy the original sheet music. There might not be an original sheet music in the first place; let alone a fitting transcription for the instrument you are looking to play. What musescore.com offers, is largely built upon hobbyists' transcription efforts.