Your confusin reaction speed with speed, Snakeman isnt faster then G5. Luffy went to G5 because he needed the speed to deal with Kizaru that Snakeman couldnt offer.
This point is irrefutable lol.
And still failed to tag Kizaru during G5 until the very very last second, while he was tagging Kaidou anytime he wanted.
Luffy needed to go G5, because Snakeman's movement speed does not allow him to play tag with Kizaru, he has no shot at keeping up with a Kizaru travelling around the island at light speed or w.e. G5 offers max speed in all departments. Snakeman lacks G5's movement speed, but it doesn't take anything away from Snakeman's attack rate and angles of attack, you're acting like Kaidou could deal with Snakeman, when
he couldn't even perceive that ish, I don't think you understand how ridiculous that is.
As for movement speed, and attack speed. If Kaidou was fast enough he could pull this off with raw speed.
Here we have Luffy attempting a snakeman barrage, Kizaru is literally miles and miles away from the island before Luffy even notices he's not infront of him. This is on an entirely different level from Kaidou who couldn't escape Snakeman's onslaught.
Then Kizaru miles away from the island, blitzed FS Luffy without Luffy being able to do a thing about it. Another feat well above anything Kaidou showed in terms of movement/attack speed.
Oda literally gifted Kaidou FS, because he couldn't come up with a speed based solution for Kaidou to escape the Snakeman onslaught. You look like an imbecile trying to argue this.