Even if you don`t rate GGG you have to rate his power, look how many shots it took Hagler to stop most of his opponents.
Who did ggg stop who was worth a damn? What elite or good fighter did he stop? Hagler stopped better fighters than ggg and fought better ones as well.
Is this how you think power works?? Who did Buster Douglas KO before Mike tyson?? Who did Rahman KO before Lewis? According to your (lack of) logic, neither Douglas nor Rahman should be able to KO those two because they weren't as great as them.
Look ay Hagler`s punches against guys he`s stopped and tell me GGG`s punches wouldn`t have the same effect, are you trying to tell me that Hagler`s opponents were better than GGG`s opponents because they all had better chins than anybody GGG has stopped? There`s no way that canbe proven, Hagler fought a lot of good fighters but they weren`t amazing, Mugabi was good but was stopped by other fighters and he was stopped at 154 v Norris, Hearns was a great fighter but it wasn`t due to his chin and he got stopped by Ray at 147, Roldan was a good stoppage for Hagler because he was well known for being tough.
I am a big Marvin Hagler fan but, I'll happily admit that GGG has better 1 punch power. However, I give the edge in stamina, combination punching, jab, ring IQ, chin, ferocity, will to win and the better resume all to Hagler. GGG is a once in a decade kind of fighter and up until facing Canelo and maybe Jacobs looked unbeatable. Marvin Hagler has a strong case for the number 1 MW of all time. That cannot be said about GGG in my humble opinion. H2H I would definately give MH the edge and believe over 15 rnds. that MH could in all likelihood stop GGG on cuts or a corner stoppage/TKO as Haglers jab could pile on a huge amount of facial damage over the distance.