And that's pretty much what Keenum is, he doesn't turn the ball over, he usually won't lose you games and usually won't win you games. He is a game manager on a team that had enough talent on D and O that he went 3-2 last year (and almost went 4-10).
He's either going to be the long term backup here or somewhere else and I hope it's on the Rams because having him take over if Goff gets hurt, which will probably happen at some point it almost always does, isn't a bad thing. Having a game manager for your back up QB is a blessing.