Not sure if that's deserved or not, but just generally the way we are, we assume good health. So I think most are assuming that if they're healthy to start the season, they'll likely stay that way

I think there's more confidence in Cam Rising because (loosely in order)

1. Rising has done it twice.  Two conference championships instead of one. Two 140+ QB ratings instead of one. Therefore easier to predict it's the norm, not a one-off ... especially after Baylor didn't have confidence Bohanon was the right guy moving forward (even if Shapen hasn't worked out great either)
2. Rising has done it more recently. 2021 and 2022, then missed 2023. Bohanon did it 2021, then wasn't as good in 2022 before being hurt and missing the back half of that season and all of 2023
3. Utah is seen as better positioned to make noise on the national stage this year, which makes him a more relevant story than Bohanon (to most - obviously we care more about Bohanon....though we do seem to care an awful lot about Rising)
4. Rising hurt his knee, Bohanon his shoulder. The general mindset for QBs is that their arm matters more than their legs so when Bohanon wasn't sure if he'd throw a football again, that was more worrying than an ACL which is sadly fairly normal in football
5. Rising had been better when both were healthy.  Bohanon's best season was 2200 pass yards, 63% completion, and 2.57 TD/INT ratio.  Rising's best was 3000 yards, 65% completion, and 3.25 TD/INT ratio.

You'll note that very little of that (except point 4) actually has to do with their injury or return from it. And on point 4, it looks like the concerns over Bohanon's arm have been answered.

But that's my guess for why Rising is getting so much more attention than Bohanon.