Neal Krawetz of fotoforensics (and others probably) disagree that C2PA "is a well thought out solution"

https://www.hackerfactor.com/blog/index.php?%2Farchives%2F10... (search his blog if you want more of his thoughts on it)

I don't have a know enough bout this but I've been reading his blog for other topics a while and he does seem to know a lot about photo authenticity.