I think backing Perez is a punt, if the wrestling fails and he just gets stuffed or reversed then what? He's stuck on the outside with a calf kick at his disposal. He's not quick Perez, he doesn't have the power of Fig, and I don't think he can control the pace or direction of the fight either.
I don't really agree with that. Perez is a pressure fighter and Fig is not a volume fighter. Perez likely has the better gas tank for deep water too. A calf kick isn't his lone stand-up weapon, it's something he used in a matchup where he knew it'd be effective. And it's hard for me to imagine that Perez can't take Fig down, I'd only be more worried about Fig's sub attempts and how quickly he can get back up, but Perez has great transitions&scrambles too.
As for the matchup/competition stuff... I mean if we're going on that, Fig has only beaten one top 10 beside Joe. Perez hasn't, but this is definitely not some worldbeating legend vs some mid-level dude at this point in their careers.