I dont think it really says that (not that I have a problem with it). Idzik also comes from Seattle and we know all about their corners...
They didn't go out and grab their corners for huge money. Sherman was a mid round pick, set to earn almost nothing.
While the Jets invested in Wilson Milliner in the first, and traded for Cro plus gave him a big extension.
Rex loves his corners far more than Seattle does. That doesn't mean Seattle aren't better, but that was just good drafting and luck.