I think this article will clear up a lot of the confusion.
CD Baby changes Terms of Service agreement to help you collect unclaimed royalties
The idea is to help artist who have not signed up with SoundExchange, but are in danger of losing royalties because of that.
If you don’t want the service regardless, you’ll be able to opt out in your CD Baby account and continue distribution like normal.
If you already have a relationship with SoundExchange, nothing will happen. The money will flow the same way it always has.
It’s only about making sure artist who don’t have representation get paid their due (and it doesn’t get paid to major label artists).