What an ass. Thanks for the explanation.
Because Francesa's a f-ing douchebag that has had it in for the Jets since last year. Specifically he got offended that the Jets said they felt they would have won the Colt regular season game last year anyway and he went off on the team, calling Rex a clown. Even before then he didn't like the 'mouthy' Jets (specifically Bart Scott) but that was where it came to a head. And during the playoffs he mocked our 'great field goal' defense when kickers started missing left and right in the playoffs.
Basically ever since that point he hasn't been able to get any Jets on his program for whatever reason, depending on what version of the story you believe - there's been about three different ones (personally I think the Jets just DID decide to boycott him, which I wouldn't blame them for since he's been totally unprofessional towards them and their fans). The reason why it's news now is because he's running a PR campaign to get 'his' side of the story out since the farther the Jets go in the playoffs without him being able to get a Jet guest on the more embarassing it is for the '#1 program' in New York.
Of course he's kept up his Jet bashing since then, and will look for any way to tweak the fanbase possible. When Braylon had his DUI the Jets were classless for playing him, despite the fact nobody else suspends their players for DUI's either, including the Giants. When LT does what he does, he's not violent, he's gotten screwed by the system but god forbid Santonio Holmes has an overblown incident on an airline with an ipod and it's more proof that the Jets are a classless organization.
I remember when Fancesa had problems with Michael Strahan and Jeremy Shockey, then with the Giants, a few years ago. They, too, refused to appear on his show.
These are all just more examples of him trying to be a part of the story, rather than just commenting on the story.