I actually have little to disagree with in what you said. Which is why I've said in numerous other posts that if an Edge Rusher is sitting there at 37, and he is clearly graded as above any offensive skill player, then they should take him. And for the reasons you said.

But......there is no reason to think that Quinn won't be able to play the position (in fact, I think he's well suited to it), and playing upright and attacking the QB from different angles without trying to fight through OTs and DTs ought to benefit him healthwise, unless his back is just too badly damaged to allow very much contact at all. In which case retirement may come much sooner than later.

But if the draft is as deep as you believe it to be in Edge Rushers, then we also ought to be able to get one past the 2nd round.
Besides: the Achilles Heel for the Rams for many years has been poor offensive output. Over the past 10 years, the BEST they have done is to be 21st ranked (one time), and the last 2 years they have been 29 and 32. And inbetween in the mid-late 20's. In other words......really, really, really awful.

So to me, it is about priorities. And offense must be the priority in this draft. Again; I do agree that if a potentially great Edge Rusher has for some reason dropped into our lap at 37, you probably take him. But what if a potentially great WR or TE drops into our laps at 37? I would likely take the offensive player.

I also feel that the offense putting points on the board is both a psychological and actual lift for the Defense.