it's been criminalized to hell by IP holders and hollywood. Such a shame they killed the best tech of the previous decade. Could have revolutionized how we distribute content, approach CDN and even streaming.
Neither of those are against the bittorrent protocol itself. Lots of software like Ubuntu is legally available on bittorrent, and I've never seen anything done to restrict that.
Even without hollywood people wouldn't have wanted to use any platform that uses their data and battery/power to share to everyone else.
It's the main reason why torrenting platforms have introduced ratios and made it hard to get invited.