Where were they drafted? They were each the best RB in their classes. Elliot was a top pick 5. Gurley a top 10 pick. But the classes in general were underwhelming. This furthers my point. The position wasn't devalued, the players over all just weren't that good. Elliot and Gurley went high because they were seen as being good in spite of being RBs. Good RBs weren't devalued. The rest of there classes were players who were not as good, so they weren't drafted as high. It wasn't because the NFL decided RBs weren't important anymore. It was the RBs were not as good anymore.
Henry had huge weight concerns coming out of college as people didn't think he could be as good on the next level because of his size.