I'm not entirely convinced that's true. The Broncos, Jets, Cardinals, Browns, potentially the Dolphins, almost certainly the Jaguars, possibly Tampa Bay, potentially the Ravens, and the Bills will all be in play for quarterbacks--and there's no telling what the hell is going to happen with the Vikings and their three-headed monster, or what in the world is going on with Andrew Luck--and the Giants, Saints and Steelers all have starters with much less playing time ahead of them than they do behind. (Brady won't retire until someone destroys his phylactery.)
Obviously some teams like the Giants will probably address, or attempt to address, their needs in the draft, but there's going to be quite a bit of demand for quarterbacks this offseason.
Silly list. Half of the teams you're mentioning will likely try and draft a QB at best, and most of them not in the 1st round. Which doesn't do anything for the glut of experienced QBs I was talking about, plus the batch of 1st round QBs that are in play. Think the Steelers or Pats (or half the teams you mentioned) are going to compete for Cousins, or Keenum, Bridgewater, Foles, etc.? Nope. Which means, as I said, more people looking for starting jobs than there ARE jobs available. Meaning most won't get nearly the money they think, and some won't get any money, or will get backup money. An odd flip from most years, where everyone needs and nobody has, so crappy retreads get decent starter money. Why even bring up the Ravens, isn't Flacco signed until 22? They're not going to toss 30M at a backup.
Off of your list, there are like 5 legit teams looking, and at least 1-2 may talk themselves into the draft given their position. THere's like 3x that many QBs looking for a gig; some of those are going to get short deals to bridge to the draft pick taking over, at best.