He's a bit like late career Alex Smith. He wins but he needs a good defense. His mistakes stick out a lot more than his good plays too. Probably because neither player really throw the ball downfield that well for big plays. They just kind of methodically move down the field and score on a forgettable 1 yard hand off to the RB.
Jimmy is 23-8 as a Niners QB. They looked liked a dumpster fire before trading for him and they're a dumpster fire any time he's out injured. Lance may be a much better QB in time but I think he's well behind Jimmy right now from what I've seen. I don't see any reason why the team shouldn't be patient as long as they're on a trajectory for the playoffs.
Jimmy's "problem" is he's like the 18th-22nd best QB in the league. Makes some good throws, can feed talented players, run the offense well. Late career Alex Smith is a great comparison. But he's proven he's not a guy who can put the team on his shoulders and carry the team. He's not going to win you games like a Russ/Kyler/Mahomes/Allen/Lamar. The super bowl was the perfect example on how big of a difference an elite QB makes in the playoffs and tough games.