I don't see old gen as being that much weaker than prime. The main problem they have is a lack of stamina typically.
The injury part is more believable.
Those three are pretty close in power for me. I don't see them as far apart, and I don't see old G as being super weak compared to his prime.
The thing with oldgen fights is that they are hard to judge. Even if logically they should look worse, Oda will always write them to look good.
So I don't see Imu as a fraud for getting a scar from Gaban escpecially since he fought two powerhouses right before.
They are , look at ray with kizaru
If he was in his prime he would have defeated him right there.
And while ray has no injuries.
Yep it like oda giving them part of their glory
Same with garp if he was in his prime he would have defetaed all the pirates in bb island .
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Nah those 3 are not close
Its just fans want their favorite to be close to each other lol .
Same with SHs Luffy ,zolo and lanji
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Imu getting scar hmm don't but its not needed to acknowledge gaban lvl.
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Also imu getting wonded from gaban doesn't tell he is fraud .