Bo hasn't even made his debut yet... and he's only scheduled to fight a bottom-feeder in Pickett (which IMO is apt for a raw talent like him). They're probably going to develop him a bit more slowly than some people think, not rush him straight to the rankings.
Pretty reasonable for Khamzat to be the favorite considering he's proven that he can compete at Middleweight against solid opposition, has defeated a perennial Top 5 guy at Welterweight, and has more overall MMA experience than Bo along with a robust amateur wrestling pedigree of his own. I mean even as someone who likes Bo as a prospect and is very interested in watching his ascension this is straightforward stuff. I would favor most top guys at 185 over him until I see way more of the dude. It's just the safer bet IMO.