How much do cover artists get on Youtube?

I occasionally watch a channel with over 2 million subscribers that does song covers and the posters recently put up a plea for people to join their Patreon. In the vid, they explain that while they have a lot of subscribers and an article recently said they make about $500k a year, the bulk of that goes to the artists whose songs they cover.

My first thought was “Even if they’re taking half, you’re still doing pretty well, guys.” But given their description of their circumstances (working McJobs to pay the bills), it must be more than that. Anyone know how much more? What’s the straight dope?

I suspect that in many cases whoever owns the rights to the song they are covering has copyright claimed all the ad revenue from the video.