It's been a while since I complained about OP, to thank you for the opportunity.
Now....So when it comes to electrical currents traveling through things, we have conductors and insulators. One example of a conductor is our feeble human bodies, being made up of mostly water. If a current of electricity strikes us, it will mostly pass through water of our bodies relatively simply. What will not be simple is what happens to our more insulating internal organs, who will get all get far more of the charge and, if it's enough voltage, kill us. An insulator, such as rubber, does not allow electricity to travel through it easily. This basic, surface level understanding means might make you intuit that Luffy, a Rubber Man, would be super effective against electricty, right?
In reality, Enel would fuck. Luffy. up. He'd fuck him up harder than he would anyone else with less effort. In the magic world of OP, if when lightning hits an insulator, it just...disappears. The lightning hits him, then it's gone. In reality, if you have electricity hit an insulator, all that means is that the voltage has
nowhere to go. So Luffy would be eating ALL that voltage thrown at him. Lightning, as you know, is really, really hot, so just imagine melting, burning rubber, except it's also a human body, and that's what should happen to Luffy. The good news is that unlike a regular human, the electrical current wouldn't fry his internal organs, atleast not until Enel melted enough of his skin to hit them directly.
Ironically, you know who would best counter Enel? That Gran fall motherfucker. He was wearing a suit of armor and, guess what, metal conducts electricity! The guy is walking around in a faraday body cage. The current would travel through his armor and down into the ground, bypassing his internal organs. Well, the sheer amount of voltage Enel is throwing around should melt almost anything regardless, but it would be more accurate than Luffy just making the lightning go away.
I'm not hugely informed on electrical science, so I might be wrong here somewhere, but I remember looking this stuff up at some point and I looked it up again to paraphrase from
here.