The two teams are in very different positions, but it's too big a risk, either way. At least the Rams have the young defense, the cap room and the running back. They have nobody to start for them, and they can always convince themselves they overpaid as a PR move for entering a new market. And they were coming all the way up from 15. Still stupid to ransom the future on one pick, but at least you can see the rationale.
The Cowboys *have* a very good starter for the next 2-3 years. Sure, if a top QB falls, you take him, but you don't trade multiple drafts away for the number two option on the board when you can sit tight with the luxury of having some time to develop a guy and take a player of Lynch's quality either this year or next without giving up the farm to do it. There's playing the game, and then there's playing it to win. Now is the time for us to fix the defense unless the QB of the future lands in our lap.