Two things, one I put on the author, one I kinda put on myself, and both are a bit hard to explain without an example:
1) I guess this can be summed up as "They (the author) should know better." One post-canon fic I read by an author I enjoy greatly had all the markings of being another favorite until the very last scene. In it, after surviving the conflict of the fic, the two main characters were all but implied to have decided to commit suicide because they felt they have served their roles to the fullest and the world no longer needed them. And it was portrayed as if they were correct in their assumption, with all of the flowery language that comes with an intended cathartic release.
I fucking hated it.
The whole scene reminded me of a teenaged first-time writer who just discovered the Downer Ending and just had to include it to appear mature and refined, regardless of how well it fits with the rest of the narrative, and it did not fit this story at all. I've read other stories by this author with darker themes, all written before this one, and they weren't nearly this corny. It's like if Spielberg went "...and that's what happened when they were Saving Private Ryan." By that point in his career, he should've known better. Same with this author.
2) I said this is a bit of a me problem, but I also lay some blame on the author. A Zelda fic I'm reading and following now is a retelling of Twilight Princess. And like many TP fics, Sheik appears as Zelda's alter ego in reference to how that aspect was planned but later dropped for the game. In this fic, "Sheik" is introduced as a separate personality for Zelda when she decides to go sleuthing. Zelda is still there and makes all the decisions, but in multiple scenes it's described that the current revelation would have Zelda panicking while Sheik allows her maintain focus, almost like a shield, and she was trained for this from a young age in case it was ever needed, referencing her predecessor from Ocarina of Time. I found it a fascinating take on the character. It reminded me of those with Dissociative Identity Disorder or even people with extremely stressful jobs who compartmentalize just to stay sane, only here it's intentionally induced in order for the fantasy ninja to operate more effectively.
At least, that's what I thought the author was going for.
When Sheik was first introduced in the story, I truly believed they were using the plural they/them instead of singular, as if there were two distinct personalities, mainly from how the author wrote the scenes. It wasn't until several chapters later when Zelda-as-Sheik gets gender-envy from a truly androgynous OC that it's confirmed it's the singular they/them. Turns out, when Zelda is operating as Sheik, it's they/them, which, in conjunction with the androgynous outfit, is supposed to make identification more difficult, or so they try to explain to Link and Midna while flustered, an emotion that seemed impossible for them to have. No mention of the laser focused training from their youth. No mention of the personality shield. Granted, this development doesn't detract from my enjoyment of the fic; amongst a bisexual Link, a trans Midna, and an entire Twili society that makes the Greater Seattle Polycule look trad, an enby Zelda fits right in. It just feels a tad bit annoying when what looked like a unique idea was seemingly reworked for shipping purposes. This development only happened a few chapters ago, though, so maybe that idea I more than likely read too much into will come back? It already gave me ideas for my own stories.