I do agree that it’s unfortunately more common to conflate the two nowadays. But not everyone that receives dissent will designate the dissenter as an asshole. At the very least I welcome well intentioned dissent as it helps find the truth.
How would discussion be swayed by zaps? In a client where there’s an algorithm that promotes zapped notes then I would agree but that’s not the case now and would be optional in the future. You still choose who you follow, not sure how people would get drowned out by having less/smaller zaps.