We know it's negative, because Alphabet has refused to ever publish it, despite doing so for its other divisions. Not to mention their overall revenue is also declining on top of that.

https://www.cnbc.com/2020/02/03/google-still-isnt-telling-us-about-youtube-and-cloud-profits.html

https://www.theguardian.com/technology/2022/oct/26/youtube-battle-with-tiktok-takes-its-toll-as-revenues-dip-alphabet