At no point g5 is faster than Snakeman in attack speed btw.
Ods restricted Luffy from using adcoa and adcoc to make it seem like Kizaru/Admirals can handle current g4.
Adhaki G5 > Adhaki g4 ~ Admirals
Kizaru was blocking snakeman attacks because he knew he can't dodge then easily.
He's lucky luffy didn't use fs and adcoc or else he'd be bloodied and weakened already