There are Fighters that their hype got derailed when they certainly just lost one bout, like Johnny Walker was hype back then but Corey Anderson stop his train, Ben Askren was a hype when entering UFC, from One Championship he was undefeated and debuting from UFC his bulldog choke against Robbie Lawler pretty questionable because he was pretty devastated by Lawler until he can get that Bulldog choke, but the hype stop when he was Koéd by a flying knee in just 0:05 Seconds by Jorge Masvidal, I think there are many hype in the UFC and the MMA back then but for me Khamzat Chimaev's hype is really legit, and I can see the guy really has potential and he is not afraid in showing it.
At the end of the day its a fight, and this is especially true in MMA; anything can happen. So, fighters losing the odd fight isn't exactly unexpected, in fact its expected for the majority of fighters. You could count on one hand the amount of fighters that are undefeated, while taking on the top guys. Khabib obviously being the most recent, but he's very much an anomaly in the sport.
Even Conor who at one point looked unstoppable, you could say that's due to the way he fights, and Khabibs style protects him a lot more than a pure striker like Conor, and while that might be partially true, if you take a look at the other wrestlers in the sport they aren't going on massive unbeaten streaks.
Therefore, I don't actually believe in the hype being derailed from a single loss. If Makhachev were to fight either Oliveria or Poirier which I personally do believe its a little too soon right now, if he was to lose that doesn't automatically mean the hype behind him should be gone. Poirer, and Oliveria are literally the two main men in the division right now.
I find as fans we can have a knee jerk reaction whenever a fighter loses a fight. In fact, this probably isn't entirely the fans fault, due to the UFC as an organisation pushing the agenda that every fight will finish a fighter if they lose, and project the winner onto bigger, and better things. Boxing also has this mentality because hype sells tickets.
Though it was proven recently that older fighters that were deemed finished many years ago, can improve, and go on to win belts. Makhachev losing against the current top 2 in the sport isn't going to realistically derail his career. Though, for his benefit its probably best to not jump in the cage with them too soon, because in the eyes of the fans it would take away a lot of the hype, however when he starts winning again that would return right away.