I mean we can get in to turnover worthy plays versus actual turnovers and stuff like that, and there's also the mess of who is actually to blame for fumbled exchanges, or tipped INTs, or completely whiffed blocks. I don't think it's a crazy assertion that they are similarly risky with the ball security when Haarberg is at 2.5 fumbles + INTs against Power 5 teams. Sims is at 3 per game.
I will 100% agree there is an objective answer to "who has turned the ball over more?", and it's Sims. Apologies if I've been unclear on that, and I realize I'm making a few different and not well-defined arguments. But I do think things like "Who is more likely to turn the ball over moving forward?" involves more than just the literal turnover results. I'm sure some paywalled site has turnover worthy plays, but off the cuff I would guess it's unlikely that all of Sims fumbles would be recovered by the defense like they have been to this point. And before Purdue, we had recovered 6 out of Haarberg's 7 fumbles - that was clearly unsustainable.
If people don't like judging by what was likely to happen instead of what did happen, I can understand that and agree to disagree. And I will admit that "likely to happen" is definitely more subjective, but I also think it's more predictive.