it is the same if you base it just on the amino acid profiles, they are both just proteins with different amounts.

I always wondered if there were nutrients we can’t measure though, because collagen is typically made from skin or bones whereas whey protein is dairy. Even though both have similar “nutrition facts” maybe there are some unmeasurable differences. Both are highly processed though so who knows.

I think the idea is that some short peptides might survive the digestion and make it to the blood stream, but I'm doubtful there's any specific benefit to collagen.

Afaik, not exactly, collagen has hydroxyproline which is attributed for skin\hair\joint improvement.