That is not the same monetization as using ContentID to add ads to all other videos with the music. That ability would be lost when an artist is not accepting the new terms.

Right, but they aren't losing the ability to monetize the content they want, as the parent comment suggests. They are restricted from ContrntID, but they can still upload and monetize video.

Personally I don't really like these changes, but let's not be disingenuous.