Yeah, because he could have done all that until whenever he wanted if he was halfway intelligent about weilding his power. He'll get this next contract, probably, but he is done after that without a doubt. Eventually, just freaking everyone raw will make everyone hate him more than they hate each other.
I think you misunderstand Goodell's role. He didn't punish Dallas and Washington for overspending in the uncapped year because he felt it was the right thing to do, he did it because Mara and Tisch and Rooney and Kraft and a bunch of other owners saw them doing it and wanted him to take away the advantage they gained.
He didn't punish Tom Brady and the Patriots for cheating because he thought they were, he did it because Mara and Tisch and Rooney and Jones and a bunch of other owners felt that Kraft was getting a bit too big for his boots, and because Jones and Snyder and Blank wanted to demonstrate that they were unhappy with him supporting their punishments.
He didn't punish Elliott for being a shithead because he felt it was the right and proper thing to do, he did it because Kraft is still pissed about the Brady suspension and wanted to get back at Jones for not supporting him through the whole thing and because Mara and Tisch and Rooney and Snyder all love putting the boot in on Jones.
All the while that these guys are playing out real life Game Of Thrones, the fans are busy pointing at Goodell as the bad guy. And you think the owners are getting sick of him? The guy is a dream employee, better than they could have possibly dared hope that anyone could be at their job. They are never, ever firing Goodell; one day he'll get sick of it and go home, because they've already made him far wealthier than any sports commissioner could ever reasonably hope or expect to become as a result of his spectacularly good performance.