By any bigger fighter. Only reason Conor has been successful thus far in the UFC is by having a longer reach and fighting smaller guys. He just sticks his arm out in every fight, rubs it into his opponents face. The only time he's faced an opponent who had a height advantage and a similar reach was Nate Diaz. And Conor lost that fight. Quite embarassing considering that Nate Diaz is just an average fighter, not one of the top guys. Conor fought at featherweight for a reason. He cut tremendous amounts of weight to fight in a division where he would have a physical advantage over everyone. That's the only reason he won. Lightweight is where he belongs but obviously he wants nothing to do with guys like Tony Ferguson and Khabib. McNugget would get mauled in an eventual comback. Dude wants no part of it and is probably scared shitless of fighting guys of the weight class he belongs in.