The Saints didn’t screw him over. They reportedly offered him an extension that he didn’t immediately find on the market, and was reportedly in the neighborhood of the contract he’s playing on now in Philly. (The Saints were reportedly offering about $8 million / year and he wanted $12 million per.)
He’s had the chance to play for competitive teams since departing here. I’d say it’s worked out for him, and the Saints avoided tying up more money in a player who probably wouldn’t have been a good value to us given the team’s shortcomings.