Are you asking if Gamboa can beat Broner? If one weight class matters? Or what?
I mean of course size matters that's why weight classes exist. But it don't really matter imo when it's only 1-2 weight classes apart. Especially 1.
A lot of these weight classes are pointless.
Say no weight limits. I will still pick a Prime Hagler fighting at 160 over every single 168 Fighter rehydrating to 175 today.
But to think that Prime Hagler can beat David Haye is just fantasy.
I will pick Prime Sugar Ray Robinson to maybe beat a Chad Dawson. But Prime Lennox Lewis will kill Ray Robinson. Not beat, but kill. Dead Ray.Dead.
Tyson and Tua are natural heavyweights, so that comparison don't mean much. In other words, if you see 5'10 Tyson on the streets, you will think to yourself 'wow that's a big guy'. If you see 5'9 Danny Garcia, you will think to yourself 'that's a skinny-average guy'