Goff is a 2nd year guy who was drafted number 1 overall.
Garappollo is a 3 or 4 year guy who has played some but was stuck behind Tom Brady, the best QB of our time.
We don't know how good Jimmy could be but first of all he has to learn the Niners offense and there is no way they can make a judgment on him the last 8 weeks of this season. No, he will be their guy in 2018 as well.