This is very different.

It runs 24/7 aongside the "ok google" detection, and as soon as it detects a song, it'll show the name on the lockscreen. So normally, all you have to do is look at your phone to get the song name [0]. This is also done 100% locally, there's a offline database of 10k+ songs which is only ~50mb [1], and gets updated regularly.

[0] https://venturebeat.com/2017/10/19/how-googles-pixel-2-now-p...

[1] https://www.xda-developers.com/google-pixel-2-now-playing-so...