Mcgregor is better on his feet then both aldo and mendes, it's not close. He is a national boxing champion and throws his punches with no effort. Aldo, is more explosive, but conor looked gigantic against chad and seemed to walk through his shots, he had his hands down chasing him at points.
His spinning heel kicks to the guts hurt him right away, from the first kick right at the bell.
Someone with wrestling and elite jiu jitsu would be his hardest test, I don't think he will lose on his feet in an exchange with aldo, mendes punches sent him flying and dropped him. Conor took an elbow and then an overhand and asked him if it's all he had. He really should be in the 155 pound division, he cuts so much weight.
He reminds me alot of Tommy The Hitman Hearns with his reach advantage, punching power and that left hand that can send anybody in the division down with one shot. So fluid and crisp with his strikes. Those kicks were brutal.
And to your second point, that was the talk going into this last match... "Mendes would potentially be a tougher matchup for McGregor" Well, we all seen the result of that little experiment. Wrestling champ couldn't do anything with him on the ground beside exchange shots and was kayoed in the second round. McGregor knew they were going to be stood up eventually and then the fight becomes incredibly one sided. He was there for a 5 round fight and Mendes clearly wasn't.
Conor did Mendes a favor by putting him away so early. Once he got up from that last takedown, the fight was over. Mendes was completely gassed and it's very unlikely he would have been able to secure a takedown against a much fresher McGregor.
A fatigued Mendes unable to secure a take down against McGregor in the 3rd would have been completely embarrassed in front of the whole world.
Conor did him the biggest favor in the world by putting him out of his misery.
I think some people are putting way too much stock in Mendes' winning that first round. As I stated earlier it was a 5 round fight and McGregor knew going in he would wear him down with body shots and eventually Chad would crumple like a house of cards.