why is adrien irredeemable?
Because the writers 110% *support* his behavior, and want his behavior to be a role model for little kids, which is why they've been pushing and romanticizing his harassment from day one, all the way through 4 seasons and no doubt they're going to up the ante in the 5th season, since That Guy is apparently leaving after s5 because of his contract.
Unless completely new writers come in, determined to fix that train wreck that is ML, and actually want the characters to be good role models for kids... It's not gonna happen.
You can't redeem a character that the writers insist has never done anything wrong, no matter how horrifying his actions are to those that look at what the show is Showing us, instead of what the show is Telling us.
Put on any episode of Miraculous Ladybug. Take off the shipping goggles, pause, breath, and put yourself in Marinette's shoes, in the shoes so many of us "Adrien salters" have experienced first hand, which is why we were the first ones to speak up:
You are a cashier at a grocery store.
You are a first responder.
You are a girl, too young, and you are constantly fighting to be perceived as professional, giving your job your all, doing everything you can to save people's lives, and... Having to fend off your coworker.
Let's adapt an episode incident, shall we?
You are rushing your parents to the hospital after your house collapsed on them-- your coworker has met your parents before, he knows them, he should care about them, but he doesn't.
You were already in the process of evacuating your parents from your house before the collapse, you and your coworker both knew about the structural instability caused by the terrorist attack-- but instead of helping evacuate your parents in the precious seconds you have to get them out, instead your coworker, who knows how dangerous and precarious the situation is, swoops in to get in your face, invades your personal space, and kisses you.
You're shocked, horrified at the violation, and flinch away--
and the distraction is enough for you to lose your grip on the safety rope --
not only do you yourself get hurt from the recoil, slamming into a wall hard enough to crack your head open, but now your parents are trapped in the collapsed building when they would have been safe and sound it your partner decided to help you instead of assault you.
While you're struggling to get your parents out of the collapsed wreck of your house, sobbing despite your best effort because you would have been there in the house if you weren't at work, you would literally be dead in your room because the second floor is completely gone, you have had them safe if only your partner didn't violate you-- and what does your paramedic partner do?
What did Adrien do in Weredad, despite having met Marinette's parents multiple times, despite apparently considering Marinette a friend, despite knowing that's Marinette's room, despite knowing his "friend" and classmate and a fucking gods damned helpless innocent civilian was probably DEAD?
Stands around watching you do all the work.
stands around despite it being his literal duty to help.
stands around despite knowing who your parents are and supposedly caring about them.
stands around despite claiming you're friends.
Stands around and only moves so he can kiss you against your will while you're trying to save your parents lives, resulting in you getting hurt and your parents being trapped in the collapsing building.
You've got a head injury, your parents are in critical condition, and your partner is just standing around watching and making no effort to lift a finger as you're trying to load your parents into the ambulance despite it being a two-person job.
If Adrien were an actual good person that actually cared about his sacred duty, let alone actually cared about the people he supposedly cares about--
Why did he actively sabotage Marienette's efforts to save her parents lives in Weredad?
Why did he not bat an eye when Marinette was killed in her bedroom when it was obliterated in the attack?
Adrien didn't know that Marienette was Ladybug, and especially with her parents frantically screaming her name, he should have been frantic to save his friend, he should have been panicked, worried at the very least--
but he didn't care in the slightest how horrifically she must have died when her room was obliterated by two tonnes of steel and fiberglass crashing through her window.
The writers don't care about redeeming Adrien, and when he pulls stunts like this in Weredad, in Oblivio, in Wishmaker, in Glaciator, in Ladybug, and every single episode? They want you to support him, or they don't even acknowledge his actions, and pretend nothing of significance even happened, so the audience watches Marinette die horrifically while her parents frantically endanger themselves trying to save their daughter and Adrien doesn't give a flying fuck, and most people won't even notice!
Go back and rewatch Weredad. Watch how Adrien behaves in canon, watch what the show is Showing us, instead of simply accepting what the show TELLS us.
Because Miraculous Ladybug tells two drastically different stories, even where they briefly intersect, it just depends: are you willing to think about the show critically and look beyond the skin-deep veneer that hides the rot, or do you want to take every thing it tells you at face value and continue to support writers who are teaching multiple generations that sexual harassment is romantic and it's only "real" sexual harassment when someone does it with evil music in the background?