This is a fair concern imo. If you're solely looking for someone who has a track record of success, Golesh simply doesn't have it and there's no way I can convince you to be happy about the hire. There's not much to debate.
If you prefer someone with a track record (like me), but are okay with hiring someone without a track record (like me), then the next question becomes: how do we distinguish amongst this group of people (those who haven't called plays before)? Just looking at the candidates who have no play-calling experience, what's a good hire versus a bad hire?
I look at a few objective factors:
(1) experience with other OC duties besides calling plays (gameplanning and implementing a scheme)
(2) coaching tree: who is your mentor? who have you learned under?
(3) Offensive Success
(4) Recruiting chops?
Golesh checks all these boxes. Golesh (1) has critical experience gameplanning and scheming, (2) has been mentored under one of the best playcallers in modern CFB (Heupel, who is far better than Jimbo in producing dynamic and explosive offenses), and (3) can take some credit for Tennesse's extremely impressive offensive output in 2021 (which was far better than AM's and almost all of FSU's offenses under Jimbo). Not sure about Golesh's recruiting chops, but that's less important to me.
Hindsight is a *****. Coley checked most of these boxes but failed. Golesh could fail. But I don't judge hires based on hindsight. I judge a hire based on whether a candidate possesses qualities and experience that are more likely, on average, to predict success. That is, Golesh is a good hire relative to another non-playcalling candidate who (1) is a position coach and has limited experience scheming/gamplanning (2) was mentored by a mediocre playcaller, (3) is an offensive coach for a team that produces ****** offenses, and (4) doesn't croot that well.