YouTube offers some different services: Google Play Music focuses on audio, by using YouTube Music we can have access to music videos, and YouTube RED is an subscription which allows to watch some premium content on YouTube. As it turns out, it's not the end of new projects of YouTube, because firm wants to compete with Spotify and Tidal.
In March 2018 YouTube wants to start YouTube Remix, which will be quite similar service to Spotify and Tidal. YouTube Remix will mainly focus on streaming music, but probably subscription will allow also to watch video clips on normal YouTube website. At this moment YouTube is close to sign contracts with Sony Music Entertainment and Universal Music Group, and they already reached an agreement with Warner Music Group.