One of my biggest issues with Rick writing of Percy and Annabeth in botl and tlo is that it only ever considers Percy in their dynamic. Rick gives zero consideration to Annabeth IMO. In fact, at times it felt as if he was going out of his way to vilify her so that he could justify inserting multiple new love interest in the story for Percy.
Unfortunately, that misogyny in the writing worked perfectly because for years the fandom has swung wildly between hating Percy's female love interest and it's only recently have I seen people rightly question some of Percys behavior towards the girls in these books. Percy rarely use to gets criticized for any of it even though he himself has some shitty moments in how he treats several people, most especially Annabeth, at certain points in the books.
And it's not just Rachel/Annabeth. In botl, Annabeth plucks up the courage to kiss Percy and he immediately gets stranded on an island (not his fault) and starts to make gooey eyes at Calypso. The timing is cringe and weird, and if the scenarios were flipped and Percy plucked up the courage to kiss Annabeth for the first time and then she washed up on an island with another guy and immediately caught feelings for the other guy people would say Percy deserved better. But those misogyny rules don't apply to Percy. He literally gets applauded for actually considering abandoning his loved ones. You cannot make the misogyny up because the reaction would have been completely different if this was Annabeth or a female character who actually took time to contemplate abandoning her loved ones for a guy she's known for two weeks. I've always found the entire Ogygia chapter weird for this (also because Calypso is a predator who is over 4000 years old hitting on Percy who was 14 at the time. WTF was Rick thinking romanticizing this?).
Same goes for the start of tlo. We're told that Percy spends the entire summer with Rachel. Mind you, Annabeth is the one who is going to be fighting in a war with him. Annabeth is the one who could have been murdered that summer fighting by his side but he prioritizes spending time with Rachel in the summer in which Annabeth could have died. And we're told he did it to escape his demigod life but Annabeth is not his demigod life, he'd be a demigod regardless o if he had never met Annabeth. And once again the excuse use to justify why he spent the entire summer with Rachel completely ignores Annabeth's own feelings in their relationship
Maybe what Annabeth needed was to not have her best friend spend the entire summer leading up to a war in which she could die prioritizing another girl. Forget shitty potential boyfriend behavior, that's just generally shitty best friend behavior. Yet I'm suppose to buy that Percy deserves Annabeth's love and affection by the end of that very same novel? I'm suppose to buy her taking a killing blow for him mid way through the novel after the way he treated her in botl and tlo? If you think about it, Annabeth spends all of tlo prioritizing Percy down to taking a killing blow for him and saving his other love interest from a certain helicopter death. And Percy spend tlo prioritizing Rachel and making it seem like Annabeth is no more special to him than the average person on the street.
Yes, we have the Styx moment and him partially giving up immortality for her but that's all in his head. When it comes to Percys actions, how he actually shows up for Annabeth in both and tlo both physically and emotionally it's comical that we're expected to think that Percy is deserving of Annabeth's love and affection by the end of the first series. How low is Annabeth's self esteem that she didn't think she deserved to be treated better than that right before they got together? Percy becoming borderline "boyfriend of the year" in Heroes of Olympus did a lot of heavy lifting with me in terms of liking him as a boyfriend for Annabeth because leaving the first series I've always felt immensely sad for Annabeth that she didn't think she deserved better than a guy who treated her like she was second rate compared to his other potential love interest, until the very end. Both Frederick and Luke clearly did a number for her because she seems to expect the bare minimum from the men in her life and Percy benefitted from that in tlo (IN MY OPINION).
And to be clear, Percy is under no obligation to return anyone's feelings......EXCEPT we're in his head and we know that he's constantly criticizing Annabeth for not being clear about her feelings while he's the one actively pursuing and catching feelings for two other girls between botl and tlo while it's heavily implied that he already has strong feelings for Annabeth. His fatal flaw being loyalty seems like nonsense when you really think about it because his feelings for Annabeth are so quickly put on pause or forgotten when it's convenient and a new girl gives him attention. Meanwhile Annabeth is only shown to have a lingering crush on Luke that preceded her ever knowing Percy. At no point since having feelings for Percy is Annabeth shown to pursue some new guy, or even her crush on Luke. Yet despite this she's the one that both the narrative (via Percys biased narration) and the fandom critiques. There are some incredibly disgusting gender stereotypes at play in Percy and Annabeth's relationship in botl and tlo that never gets addressed down to Percy having multiple other love interest and Annabeth for some reason having none. But people don't ever want to address the misogyny there because to do that would be to critique Percy via the writing.
Part of the problem with Percys narration is that he's rarely challenged by anyone in the text over some of his behavior towards Annabeth while he passes heavy judgement toward her in his internal monologue. That judgement in turn unjustly influences the reader because he's the narrator. A better writer would have written that dynamic better in the lead up to them getting together. A good comparison to this where a protagonist bias and judgement is challenged while not vilifying the protagonist is Katniss in the Hunger Games. Katniss can be very judgemental and lacking in empathy in her narration especially when it comes to her relationship with Peeta, and even Gale. But then you have someone like Haymitch who is shown to constantly challenge some of her biased thinking and give a "consider how the other person feels" to combat the fact that the audience is not just getting Katniss's biased view on things in their friendship/relationship. Suzanne Collins does that while never villifying Katniss. But who does that for Percy when it comes to Annabeth? Absolutely no one. And it would have been easy to write a scene between Percy and Grover or Beckendorf or Sally, or even Paul where some of his own judgement and bias about Annabeth's feelings in botl and tlo were challenged so that his narration isn't just his own bias being used to poison the audience against Annabeth to justify his treatment of her when he had other love interest. Percy at no point is asked to see things from her perspective when they're at their worse in botl and tlo. It's terrible characterization and very biased writing that seem intentionally set up to coddle Percy and vilify Annabeth.