The article never says teams around the league feel the Cowboys and Saints won the draft. Far from it, in fact.
They say they think right now that the Cowboys and Saiints are the two SB favorites from the NFC. But that's not due to "winning the draft". From the article, it only means that these anonymous team officials feel both teams helped strengthen themselves in the draft and that other teams didn't overtake them with their draft picks to change their minds.
This isn't from anonymous team execs (and I swear I'm not trolling lol), but here's a decent reprentation of what a cross section of --ahem-- "experts" feel about each team's draft: