It all depends on whether he can stay healthy and history shows that he hasn’t been able to do that.
Another thing. Rams blockbuster trades have included a QB and a CB. Two positions of normally good longevity so better odds of consistent health and continued production. Burns would have been another such good risk.
49ers will look like geniuses if McCaffrey bucks the odds and remains healthy. But if he can’t this is gonna blow up in their face.
As I’ve said before, I much prefer that Rams invest in another position with their scarce resources.