I would be surprised if there were any human input in those songs at all. For one thing there's just too many of them.

AI music has come on a lot, to the extent that you can't really tell whether it's used any real instruments or any humans. The biggest tell is usually that the music and lyrics are very dull.

Did you hear the AI-generated band Velvet Sundown? "They" have released a couple of very popular albums. They sound a bit Tom Petty, a bit Neil Young... they are an AI version of a classic early 1970s country-rock band.

They are very boring but some people clearly like boring...

Here's a link to one of their songs:
https://www.youtube.com/watch?v=BzX1YFZW0jc

I heard an AI-generated soul singer the other day and I honestly wouldn't have realised it was AI at all, it just sounded like 1990s-style "nu soul" singers like D'Angelo or Eryka Badu.

I do think folk music has a huge virtue and strength in this ugly new world, in that its backbone is live music. And that live music is participative in a way that very few other genres of music are - the performer often is the audience and vice versa.