Publications and grants are the currency of academia: if one doesn't have a recent publication record, a hiring committee doesn't have a way to gauge one's performance and capabilities as an academic; if one doesn't have a history of getting grants, a hiring committee will be (rightfully) skeptical of one's ability to bring in money. Excepting teaching schools, one is hired for one's abilities as an academic researcher to bring prestige (through publications and PR) and secure grants (along with that sweet, sweet F&A money). To get grants, one needs publications and preliminary data. One also needs grantsmanship skills, and one only gets those from direct experience.

A YCR "fellow" (or whatever it'd be called) would probably not be a competitive candidate for an academic position. It's not because they weren't in academia, it's because they will likely not have the work product used to measure performance in a academic setting. A hiring committee is not going to risk department funds on someone with a non-existent track record when there's a line out the door of other candidates.

I think OP is correct in perceiving that selecting YCR would probably close the door to a future in academia. I will also predict that YCR will have difficulty hiring top academic talent.