I think what' bothers many fans, myself included, is that it's pretty clear the there is no one on the roster, or available next year via free agency or draft who has the arm talent or knowledge of the offense that Goff has. (the contract was not a bad decision but our hands are tied a bit) Like it or not, he is our likely starter next year as well. It seems as though his ceiling is a Jimmy G, Kirk Cousins, Alex Smith. Flacco, Matt Ryan type of range. - A solid NFL qb who can take a good team to the playoffs and possibly the superbowl, but not someone you can ride when the chips are down. There are so few of those guys that ever come along and can do it long term.
So every week, we cross our fingers and hope for the best and hope for a great performance from all 3 phases of the team. Deep down, we know - if something's not going right - Goff is probably not going to will this team to victory.
That, to me, is why his inconsistent play is so frustrating. He is all we've got, this year and next, for better or worse.