NOT AN ASSPULL
ENEL IS LIGHTNING
LUFFY DIDN'T USE HAKI TO TURN OFF HIS LOGIA FORM
Difference is that Enel's a person that's capable of turning into lightning. As with any other logia user you can nullify their intangibility with either haki, sea stone, or their natural weakness.
Lightning itself is a discharge of electricity, not a person, and would function like Big Meme's elemental homies in that neither sea stone or haki would affect them, and in lightning's case if it gets in contact with rubber it would simply disperse since it's not some meat bag with a devil fruit, but simply plasma, and therefore Luffy shouldn't be able to hold it.