I dunno, still feels like a bad match-up for him here. At Heavyweight the thing that made him notable was that he had fast hands, decent footwork, and hit fairly hard despite his size. But I jumped off his hype train long before Lewis, Blaydes, and Rozenstruik put it on him. I saw the writing on the wall as soon as I watched Old Man Shamil -- who was like 40+ years old at that point and coming off a 2-year layoff with multiple injuries/ailments -- put an absolute boxing clinic on Chris for most of the first round. Chris couldn't find his range or timing at all. He was running face-first into counters, getting picked apart on the outside, swinging at air, and just looked really bad until he finally sat Shamil down and managed to swing the momentum in his favor. I faded him in every fight after that even though he managed to find the KO against Shamil.
Hard to say how he'll look at 205. It's probably where he should have been all along in the grand scheme of things, but at the same time will his speed advantage even be all that noticeable against Light Heavyweights? He was "fast" in comparison to plodders like Oleinik, Porter, and Nascimento. I could see him having a slight advantage in footwork and hand speed in the pocket over Khalil who has a very "rooted" style, but damn Rountree is explosive when he wants to be. And he hits more than hard enough to hurt Daukaus. Rountree has something like eleven knockdowns and five KO/TKO victories in the UFC, whereas Daukaus has been finished by strikes five times in his pro career. It's not even just the power in Khalil's hands that Chris will have to worry about, but also his knees, elbows, and low kicks -- the latter of which will be murder for a boxing stylist like Chris.
I've seen some people suggest that Chris will just try to grapple Khalil... he'd be wise to attempt it, but I don't have much faith in him pulling it off. Yeah Khalil's been fed a steady diet of strikers and has struggled badly against guys who grappled with him like Cutelaba, Pedro, and Sanchez (though he just about killed Paul Craig back in the day). But I am not convinced Chris has it in his skill set. He hasn't attempted a single takedown in the UFC yet and has zero wins by submission across his pro and amateur career. There's a lot of talk about his BJJ Black Belt and how he's always training with his brother on the mats at Martinez BJJ... but I need to see it in the cage to believe it. Khalil, to his credit, has stuffed all five of the takedowns attempted against him lately ever since Cutelaba brutalized him.
Short of Chris showing an entirely new wrinkle to his game with the offensive grappling or blitzing Khalil in the pocket with his boxing to catch him with something nasty, I see Rountree finishing this fight by KO/TKO inside of two rounds.