Frankly, unless Davis absolutely wows Rams brass in camp, he's gone. He didn't demonstrate enough to be worth keeping before. I think Gilbert was drafted on potential. If they just wanted a camp arm, there are plenty of UDFAs for that.
That said, I can understand in not making the 3rd QB active for every game, but I strongly believe he needs to be on the roster. It's not about whether you can get some guy off the street that's arguably just as good. I want a 3rd QB available that has been in the camp and knows the offense (and hopefully can develop down the line into an asset as well). Sure, the season is likely over anyway if he has to play, but at least there's a hope of something if you don't have to dumb down the offense because he wasn't here. This isn't Madden where you can pick guys off the street and they instantly have full competency in the offense (and no issues).
As I said, Gilbert has received a lot of hype as someone who can be developed. I really don't feel he stays a Ram if they get cute and try to stash him on the practice squad, and boom, that's a wasted 5th round pick.
But in the end, this is just a matter of differing opinions between two people who don't get votes on the matter. No matter what Fisher & Snead do, one of us will think they're right, and one of us will think they're wrong.