Roger Sexton from The Amazon would normally be this for his homophobia and sexism, but his boot episode is so devoted to setting him up as a fool walking blindly into a fall that many people feel a little sorry for him, or at least treat it as an Alas, Poor Scrappy moment.
Rob Mariano, Phillip Shepherd, and John Cochran can be found in the YMMV Creator's Pet section.
Richard Hatch, Sue Hawk, Gervase Peterson, Jerri Manathey, Silas Gaither, Lindsay Richter, and Coach Wade have become Vindicated by History, see that Survivor page for details.
Despite ideally each castaway providing the material for their own edit, the likes of NaOnka Mixon, Colton Cumbie, Bradley Kleihege, and ESPECIALLY Dan Spilo are too much of Hate Sink castaways for them to qualify as unintentionally hated castaways.
Any castaway who is hated for actions off the show, but not for anything on the show, as this goes beyond the scope of the show.
Brandon Quinton is the most universally disliked person from Survivor Africa for his extreme whininess lazy and demeaning attitude towards everyone, especially Frank who was only shown to dislike Brandon for his aforementioned behavior. Some people at first liked his devotion to his friends to the point of Lindsay crying about leaving him, only for him to say how glad he is that Lindsay is gone at the start of the next episode and how whiny she was, before talking about selling his friend Kim out. This is only compounded by his delusions he's a good player after turning on his own alliance despite having the numbers, costing him the favor of everyone except Lex.
Sarah Jones from Marquesas is disliked for being putting in no effort in either the challenges or helping around camp. This is compounded for bringing out the worst in her showmance partner Rob Mariano (who would go on to get a better girlfriend), with her one good moment being her "Cleopatra entrance". Many were relieved she was screwed over by the tribe swap.
Jenna Lewis in All Stars is one of the earliest of the more infamous examples. In Borneo, she was well liked for her storyline of being a single mom, then getting disposed of by the alliance. In All-Stars however, she becomes the face of the "Winners can't win" mindset that caused most of the interesting characters people wanted to see to be voted out, narcissistically declaring that the winners needed to "get off their playing field" (Effectively saying the All-Stars had no place on All-Stars). Additionally she was consistently a negative presence, bad challenge performer, and generally had poor gameplay, cumulating in her refusing to try to save Rupert, resulting in both of their eliminations.
James Miller from Palau gets no respect from the fanbase for his frequent sexist, racist, Islamophobic, and homophobic comments. It is worth noting that a large portion of viewers found him hilarious at the time, though this opinion is now generally agreed to be Values Dissonance.
From One World, we have Alicia Rosa. While not as infamous as Colton, she was known for bullying her fellow contestants, including comparing Christina to her students. She is a special education teacher by the way.
Will and Dan from Worlds Apart are loathed by fans. Dan is seen as a disrespectful, misogynist jerk, with him becoming even more hated when making light of Shirin's history of domestic abuse and trying to compare it to him being adopted, which had Jeff Probst call him out on being entirely different things. Will was not one, but firmly planted himself as one of the most hated contestants of all time due to his morbid, horrible attack towards Shirin, a victim of domestic abuse (which he knew about), telling her things like nobody loves her, nobody wants to see her, and his most commonly used, that she has no soul. He continues to insist that he is right about her, that he has nothing to apologize for, and that he's a good Christian man who just calls things as he sees them. To say people, especially Christian people, find Will to be lower than scum is an understatement. With time however, Dan's hatedom has calmed considerably, and has become more controversial than anything.
After Cambodia, Tasha has become this due to her condescending and arrogant attitude near the end of the game (calling fan favorites Keith, Kelley, Abi, and Kimmi goats undeserving of making it to the end despite the fact they had been voted on by their fans just like everyone else). Which made it all the more hilarious and ironic when she received no votes at the end and the jury called her nothing more than a pawn in Jeremy's alliance.
The pair of Jason and Scot from Kaoh Rong due to their bullying towards Alecia early on and their actions in Episode 9 sabotaging the tribe and dumping water on the fire, as well as being a bad influence on Tai.
From Millennials vs. Gen X, both Figgy and Taylor received some flak for getting into a showmance that everybody ended up knowing about, which is usually frowned upon on Survivor since having everybody know about you are in a power couple together puts a target on you and people quickly got tired of their showmance. It doesn't help much that Mari got voted out instead of Figgy during the first tribal council for the millennials along their showmance seemingly being rushed as they got together five days in the game and they even told Jeff they wanted to get married on Day 18 (which makes it very ironic that they broke-up after the show). Even more so after Figgy got eliminated when it was revealed Taylor has a pregnant girlfriend outside the show and Figgy was only using Taylor and never loved him. Taylor is receiving even more hate for being a Jerkass and his immature behavior, most notably stealing food from the merge feast with the excuse that he was hungry, when TWELVE other people were hungry. It doesn't help much that Taylor managed to be a total idiot in the game.
Jeff Varner gained a considerable amount of hate after Episode 7 of Game Changers for outing Zeke as transgender as a game move, which was seen as a personal attack on him.
From David Vs. Goliath, Jeremy has become this. While he was well-liked during the first two episodes, many people stated to dislike him after he stated that nobody would attend Natalie's funeral if she were to die tomorrow during his boot episode. Many fans, who had previously liked him for being entertaining, no longer find him endearing or likable.
Elizabeth Beisel and Missy Byrd from Island of the Idols eventually tanked their popularity by weaponizing Dan's inappropriate behavior to benefit their games and then defended him against Janet, who they had gone crying to in the first place. While some are somewhat sympathetic to Missy, as she did genuinely feel uncomfortable about Dan's behavior and she did admit to getting caught up in the heat of the moment on twitter, Elizabeth is shown to be completely cold and callous, citing her exaggeration of his behavior as a joke and being incredibly rude to Janet after she had shown her genuine intent to help the women.
Lauren also received a decent amount of hate. From her calling Elaine too stupid to have an advantage in episode 6, crying within that tribal council when Elaine does have one, not being very interesting outside of her negative moments, and admitting that that she doesn't care about the situation with Dan because it didn't happen to her, it's not hard to see why.