Neither QB is going to put it all together and become a well rounded QB, I think a big factor right now is looking at the expectations vs. reality for each one.
Sims was brought in to be The Guy. He has tons of experience, he was the assumed starter from day 1, he was a face of the program, big NIL deals, conference media day, etc. Then whether it was weird luck or jitters or whatever, he played two of the worst games anyone has ever seen before getting hurt.
Haarberg, on the other hand, looked absolutely terrible in the spring game, and I felt pretty certain we would never even see him take a snap at QB in a real game. But then he got his shot and ran with it, literally, with a full head of steam. He's making mistakes and his passing game is ugly but he's scrappy and we're winning. That's a pretty simple reason to want to stick with him.
Maybe Sims has more talent, I guess? I mean he's consistently been a less than 60% passer throughout his career, so there's not a huge difference there. I don't know, for me, the biggest difference is that the ball is bouncing our way with Haarberg so far and he plays with confidence. That's about it. I can't really get onboard with benching the QB who has been 3-1 just because there's a chance that at some point he will have a game that is as bad as the 2 games that the other QB has started... It just doesn't compute in my head. Neither option is much better than the other, I just wanna ride with whoever seems like they can win 3 more games baby.