As far as I know Clone Hero and YARG are the best options going now. They both support guitar/ bass, drums, and keyboard, although only YARG has vocals.
YARG is still in development but I haven't had any problems with it. There's also support to download venues, though I haven't messed with it so I don't know how well they work yet. I'm also guessing there will eventually be support for characters at some point, but I haven't hear anything officially. They also release on Linux.
Clone Hero has a full release and the developers are still active. As far as I know there's no venue support, although some people set the songs' music videos to play in the background. It also looks like they only release on Windows.
Both of them come with a handful of songs, though you can download a ton more. They use the same files so you can have both pull from the same library if you want. I can't remember where I found the links anymore, but I have the tracks for all of the Rock Band and Guitar Hero games that had a full band, plus other random songs I got from https://rhythmverse.co/ and https://www.enchor.us/ The songs for the Guitar Hero games that were just guitar and bass are out there too if you don't care about drums, keyboards, or vocals.
Usually when a sport needs music the athlete or team plan a routine around a song. Some might choose a song that's well known in their country but not universally known. If it's a folk song it might come off as royalty free.
With the breakdancing they had live DJs cutting songs together and the dancers had to adlib their routines. According to this article the Olympics licensed around 400 songs for the DJs to use. Since each battle used multiple songs you're going to hear more tracks that you know and forget about the ones you don't.