It's clear you do not pay attention to the story.
Luffy had 1.5 years worth of training by Rayleigh in an island worth of very powerful animals. He developed Bound Man in the middle of the timeskip and when Rayleigh left him 6 months ago, Luffy sure improved his skills even furthermore.
Snake Man is a power up of his timeskip training, hence no asspull PU.
You are pretending to be dumb to troll? or you genuinely didnt even bother to read what i said?
I will repeat myself just in case...Oda keeps adding new forms of G4 at every damn fight Luffy gets, we saw one vs Cracker, we saw even another one vs Katakuri and we might even see goddamn G5 in this arc.
This is a classical case of asspull powerup, adding a new form everytime the character struggles, dosent matter if Oda tries to justify it with "he had it since the timeskip" in the end of the day its just oda's justifying a new powerup he pulled out of his ass, like dragon ball and its goddamn super sayian forms, every damn villain requires a new transformation to beat, and its the same with Luffy. Sanji's diable janble and Zoro's Asura might also make no sense just as much as Luffy gear's but at least they dont show new variant of it every damn time they fight someone.