First of all, I'm sorry that I don't know how things work..

Apparently a music can have "Content ID", that can un-monetized a video on youtube. I did give the credit to the owner in my game, but youtube doesn't know that..

This 1.1 update replaces 2 musics that have "Content ID" on it. So all musics should have no problem.

IF

You're a youtuber / content creator that plays on version 1.0 then receive a "Content ID" thing and get the video non-monetized, here's the link the music creator profile

https://pixabay.com/users/geoffharvey-9096471/

On the profile page, you can see this

"If you credit me in your youtube description: 'Geoff Harvey - Pixabay', it will ensure you don't get any Content ID matches and I will look out for your channel and give you plenty of thumbs-ups."

Another not so important notes for content creators,

You're free to upload a video for my games anytime, anywhere. Do not worry about embargo or planned schedule before release.

I just love making games and I'm happy that people can enjoy my game.

ELSE

It doesn't affect any gameplay, nor is it game-breaking, though..

1.1 Content ID · Master Healer Kale with useless party patch notes · SteamPeaks