james and snape did not have a rivalry. it was bullying.
james & sirius started on snape just because he said he hoped lily would be in slytherin with him- when both snape and lily were strangers to them.
sirius saying he knew loads of dark curses before he even came to hogwarts could be true, but they didn’t know that when they started bullying him, and it wasn’t one of the reasons.
james says, even in 5th year, when snape is friends with death eaters and involved in their ideology, that his only issue with snape is that he exists. a sarcastic comment i’m sure, but it’s not like they were assaulting this boy out of the goodness of their hearts, or that would have been their immediate defence when people took issue with it.
lily says that james goes around hexing everyone for fun in the corridors, and he doesn’t deny this. if it were a rivalry, it would just be snape. if it were because snape was a death eater, only other death eaters would be targeted, which lily would not have such a problem with because she took issue with snape’s friends to his face- and once she thinks someone deserves to be bullied, she doesn’t step in.
lupin corroborates this, claiming lily did actually like james once he “stopped hexing people just for the fun of it”. unquestionably, snape was not a target because he was a wannabe death eater- regardless, that wouldn’t justify the prank or the assault, but it makes it all so much worse that he wasn’t targeted for any of his own actions, only for things he can’t change.
we never see snape initiate a fight with the marauders.
sectumsempra was almost certainly invented after the marauders almost killed snape and after they sexually assaulted him in public. it doesn’t seem to be the spell snape slashes james’ cheek with, because sectumsempra makes you gush blood very quickly. also, outright aggression is not in snape’s character- every spell he invented has a counter-spell, and the only time he uses physical violence is when he catches harry watching the memory of his assault. snape definitely didn’t invent sectumsempra for fun, nor did he use it on anyone in school- do you honestly think of all the things sirius likes to bring up against him, he wouldn’t mention sectumsempra if it had happened? sectumsempra is, no doubt, incredibly dark magic, but it seems to be, pretty clearly, a last resort.
“[Sirius] became very still, like a dog that has scented a rabbit. // ‘Excellent,’ he said softly. ‘Snivellus.’” - an explicit comparison of snape as sirius’s prey doesn’t exactly scream fair fight.
“Snape reacted so fast it was as though he had been expecting an attack”- combine this with his walk earlier in the memory being described as “twitchy”, and it becomes very clear that the ever confident marauders felt much safer in snape’s proximity than he did in their’s.
harry, from experience, recognises snape as a victim, not a participant.
lupin claims that snape “never lost an opportunity to curse james so you couldn’t really expect james to take that lying down, could you?”; once again, we don’t have any actual proof of snape starting a confrontation, but that doesn’t mean he never did. however, we do have proof that the marauders started antagonising him from the get-go. to use lupin’s own words, you couldn’t really expect snape to take that lying down, could you?
lupin also says that he should’ve told james and sirius “to lay off snape” because he thought it was “out of order”. so, regardless of his claims about snape actively hexing james at every opportunity, he knows that it was wrong.
when sirius mentions that snape was “up to his eyes in the dark arts” harry responds that even if that’s true “he just attacked snape for no good reason”. it was not some twisted punishment, and harry, a victim of bullying, knows this.
1 vs 4 isn’t a rivalry. “remus was just a bystander” 1 vs 3 also isn’t a rivalry. “peter never really joined in” 1 vs 2 still isn’t a rivalry. especially when those 4 / 3 / 2 boys have the majority of the student body on their side.
harry and draco do have a rivalry. they only ever face each other alone or in their trios. draco, awful as he is and becomes, doesn’t immediately target harry- he attempts to make friends with him. not pure intentions, no, but not victimising: it’s seemingly an attempt at making connections with the harry potter.
draco does target ron and hermione for things that they can’t help, as the marauders do with snape. however, draco never goes out of his way to attack ron or hermione. if they’re around, he’s undoubtedly foul towards them, but they’re more of an inconvenience to him when he’s trying to goad harry into a reaction.
basically, harry and draco have an equal power balance between them. snape and the marauders did not. and never did harry or draco do anything to each other on the same scale as the prank and the assault.
