This fucking guy
My villain origin story is people claiming that Riley's biggest crime in the series was being boring. He wasn't just boring. He was a passive-aggressive chauvinist who the show bent over backward to defend. A while back on Reddit, I made a list of reasons why Riley sucks. This is that list, and I'm adding to it.
The only reason he punches Parker is because Parker is mouthing off about a girl Riley likes. Everything about this interaction suggests that Riley has heard him say similar before, and hasn't cared until the woman in question was someone he had a vested interest in.
He calls Buffy stupid for not wanting to date him (if this guy slid into your DMs and called you stupid for turning him down, lbr, this would not lead into a healthy, lasting romance)
He immediately puts himself in competition with Buffy. Even at his most inoffensive, he says things like "I don't even know if I could take you."
He has an inherently chauvinistic view of the world (established in The Initiative)
He is upset that Buffy had a significant relationship before she knew him and assumes Buffy boinked Angel in The Yoko Factor
He uses abuser language to excuse his shitty behavior like, "I love you so much I can't think straight."
He decides that Buffy doesn't love him all by himself
When he decides that Buffy doesn't love him, he confides in Xander and doesn't communicate his relationship issues with Buffy
He wants to help Buffy but only in jobs that are "manly." In No Place Like Home, for instance, he nopes out when Buffy suggests he help with the spell to identify what might be wrong with Joyce. Even if there wasn't a lot for him to do, he could, idk, stick around to be moral support for his partner who is trying to figure out what might be attacking her mother. That seems like a pretty standard partner thing to do.
He gets upset that Buffy "doesn't get all worked up over him" the way she did with Angel when "getting all worked up" in CONTEXT means "isn't constantly miserable."
He is sad boi at Buffy in OoMM for also prioritizing her mother's health after she believes Riley is healed rather than sticking around to play nursemaid
He wants Buffy to show emotion over Joyce at a time when Buffy literally cannot (if you've never had a parent in the hospital with a life-threatening illness, maybe you don't know that there are times/places to break down and "in the hospital" where you're supposed to be strong isn't one of them)
He doesn't care that his girlfriend's mother is sick, possibly with something life-threatening; he cares that he got to be the hero of the piece, the shoulder for Buffy to cry on. His only reaction to any of that was to be hurt that Buffy didn't respond the way he thought she should; no concern for her well-being or Joyce's, just Riley getting his feelings hurt because he wasn't the center of Buffy's universe or the rock for her to lean on when all went to pieces
This is further confirmed by the way he just doesn't mention Joyce's absence at all in As You Were. When he leaves Sunnydale, it's after Joyce has had a successful operation. He returns and she's not there and no questions? No condolences? It's because he doesn't care.
He doesn't ask about Buffy's death when she lets him know she died.
He starts separating himself from the Scoobies and then gets mad for not being included
He literally cheats on Buffy with vampire sex workers (there are people who say they were not sex workers, but in a show where monsters are metaphors, you have to be especially dense or willfully obtuse to not realize this is what they are)
Riley intentionally puts himself in a position where he might be killed or turned specifically to SPITE BUFFY, which demonstrates his lack of consideration for what she might have to do later if things go bad
Riley blames Buffy for being roofied by Dracula (again, monsters as metaphor)
He never apologizes or owns that he was unfaithful
He blames his infidelity on Buffy, actually
The first time Buffy learns Riley isn't happy, she's told she should've seen it, which is classic victim blaming and happens from Xander AND Riley (and a good amount of fans who want to excuse that behavior)
He is fine with torturing sentient creatures, and in fact had a stake made specifically so he could torture vampires without killing them
He goes behind Buffy's back all the time
Riley was not boring. If he were boring, he would be inoffensive. Dull to watch but not rage-inducing. But he is rage-inducing because, despite all the passive-aggressive gaslighting bullshit he gets away with, people in this fandom still believe he was "Buffy's best boyfriend." That she was to blame for the deterioration of this relationship. That he was the healthiest of the Buffyverse men. The show does, too. That's why Xander (Wh*don's mouthpiece) gives that sanctimonious little speech to Buffy (the audience in this case) in Into the Woods to scold us for not treating Riley better. Then they double down in As You Were to make Buffy fawn all over herself to let this gaslighting asshole off the hook for everything he put her through.
Riley's sin is not being boring. It's that he was actually awful. Wh*don himself once called Riley a "healthy relationship" for Buffy, and if that doesn't tell you something, there's no talking to you.