Different story for each of them, imo.
For Rodgers, its an ego thing, he loves being the center of attention, being on McAfee's show. He ate up all of the attention this off-season on will he or won't he sign with the steelers. He's been doing the same thing, for years. Sending out tidbits, he might retire, or leave.
I've heard differing news stories regarding the steelers in general. There defense is looking stout, but Rodgers has not looked sharp. Its only preseason and the fog of war is such that we'll not really know anything until the season starts - even then it will take a few games for us to see how teams are really good or bad.
As for Cousins, while I'm sure he was disappointed in getting benched and not traded, I think he's content to just keep collecting $1,588,235.29 game checks for holding a clipboard. His guaranteed salary drops to 10 million next year so the falcons have lots of options that wont be financially painful. Who knows another QB could go down this season and give ATL an offer they couldn't refuse for cousins.
I wouldn't be surprised to see him try to sign with another team next year.