Do you mean having all DOIs for all referenced papers included in the pdf metadata somehow? From my experience, authors don't know LaTeX well enough to do that. Half of them don't even read the submission guidelines that clearly say not to put page numbers on the camera-ready paper; they're never going to understand complicated metadata commands...
Improving metadata coverage is a different issue than changing business model. Objectively, one's easier to implement than the other.
It is indeed tricky getting ~5,000 publishers to provide optimal metadata, but it's a good thing to have an industry-standard platform to do it in.
(I work at Crossref)