I dunno, different stratospheres IMO. I think people misremember Ngannou being "exposed" by Miocic. Francis had already shown the ability to grapple at at least a fundamental level prior to fighting Stipe. He had stuffed the majority of the takedowns attempted against him in the UFC by the likes of Henrique, Mihajlovic, Hamilton, Overeem, and Blaydes prior to getting to the title fight. He also submitted Hamilton and had a history of taking dudes down on the regional scene and submitting them prior to turning into this ridiculous KO artist. Stipe just put on a really educated and high-level performance against him that others up to that point hadn't been able to match. Yeah, Ngannou's defensive grappling leveled up after the Miocic fight but even before that it wasn't a zero... and he was also in his physical prime at 31 years of age at the time before going on to train at a great gym.
With Despaigne, you're talking about a dude who's about to be 36 and insists on training with Alex fucking Nicholson of all people despite the fact that he's in South Florida, i.e. the Mecca of amazing MMA gyms to choose from. He had never even been given the chance to show off his defensive grappling before and the first time he did? He fell way, way short of the mark. And this wasn't Karl Williams or Valter Walker or Mo Usman or some other person with a reputation for being an oppressive wrestler & top game sort of guy... it was fucking Waldo. And for all people making excuses about how "Acosta is the more seasoned MMA fighter and he was just showing the value of having a well-rounded game and more experience in this sport!" That... doesn't really track. The entire narrative surrounding Acosta ever since he entered the UFC is that he's a one-dimensional boxer who relies overmuch on either flicking his jab or loading up on massive, telegraphed fastball punches. He's never learned how to deal with low kicks, doesn't have a kicking game himself, has gotten outwrestled before, and prior to the Despaigne fight he had never completed a single TD inside the Octagon (attempted only one, mind you). Waldo is fresh off a performance against Arlovski (who belongs in a nursing home at this point), where he looked absolutely awful and every bit the unrefined, raw "prospect" himself.
So to have Despaigne getting exposed by a dude like that... it's not promising for his trajectory if you ask me. Don't get me wrong, I'm sure he'll be able to catch and chin a few more guys if he sticks around. Especially if they're strikers. He is fast and hits like a truck. I also wouldn't be surprised if this loss lights a fire under him to channel some of that Olympian athleticism into his endeavors in shoring up his grappling -- especially if he puts in time at ATT or Kill Cliff (where he should already be...) But I just don't see him amounting to much in the long term.
That's fine, though. I only ever wanted fun Prelim bangers out of the guy, lol. Give him Diniz or one of the Tafa brothers next for all I care.