Yes and no, IMO.
First, and this is particularly true if Ferguson wins, a rematch could be gigantic. Tony’s most likely paths to victory involve a comeback victory by attrition or possibly a slick sub—it isn’t going to be Usman vs Woodley. And Khabib is 28-0, so anything short of a wipeout is going to leave him in good position to request a rematch.
Secondly, Justin Gaethje is incapable of being in a boring fight and he’s become a huge fan favorite. He’s one more win over Cerrone away from warranting a title shot. Once again, this is more attractive if it’s Tony with the belt, but people will still tune in to see Gaethje try to solve the puzzle. Unfortunately if Khabib dominates Tony it pretty much answers the “what about a guy who keeps coming” question, and basically leaves us with, “but Justin was an elite wrestler” prayer. But it’s still fun.
Third, people won’t like this but McGregor is always one spark away from being back in the picture. If they do something like Conor vs Poirier and Conor sparks him again, he’s back on the map. And purely for the big drama show a rematch would be compelling television.