In terms of why I don't ship Reylo, there is something, among other things, that sees the idea of women being men's caretakers (or anyone being anyone's caretaker romantically) distasteful to think about. It is unfortunately a common theme in shipping Reylo, the idea that Rey would have been Kylo's caretaker, as well as the mother to his children. Indeed, with exceptions, Reylo shippers seem to think that there's something freakish about the idea of women who don't have children. I recall one saying that women's bodies are meant to bear men's children. While we certainly have the equipment, trans men do too. Non-binary people no doubt have it. There's no doubt more. And furthermore, women aren't obligated to be mothers. There are women who can't afford it. There are women who, say, have difficulties getting pregnant or can't get pregnant at all. (Seriously, we roasted Joss Whedon for his questionable line to Black Widow in Age of Ultron, and somehow we're nodding along to the idea that women are automatically babymakers? But I digress) There are women who aren't ready for it, because they might be working through college or having a career. There are women who, dare I say it, don't want to. If a woman wants to have children, more power to her. And if a woman doesn't want to have children, more power to her as well.
It is possible, of course, that the matter of Reylos' reactions to people who don't want Rey to be a mother are rooted in a backlash against extremes -- back in the 2000s, the childfree crowd could be vicious to people who had children. It wasn't restricted to real life either. I remember one post about Revenge of the Sith that referred to Padme as a "walking womb". While they might have been referring to her role in Revenge of the Sith being drastically altered in comparison to The Phantom Menace and Attack of the Clones, their phrasing was tactless at best. Feminism is fundamentally about choice. If you want to have children, who's to say you shouldn't? And if you don't want to have children, who's to say you should? And if you're uncertain, who's to say someone should pressure you one way or another? (To say nothing of men who don't feel ready to have children, or simply don't want it)
There's also the matter of Rey being Kylo's savior. Much meta focused on Reylo focuses primarily on Rey somehow rescuing Kylo from himself. There is something uncomfortable, for me personally, about the idea that women are basically men's mothers. To quote Alanis Morrisette's "Not the Doctor" (which I didn't get when it was first quoted. I do now), Rey isn't Kylo's mother. She didn't carry him in her womb for nine months. (And given that they have a ten year age difference and he is ten years older than she is, it would be impossible without the aid of time travel, and Han somehow cheating on Leia with a girl young enough to be his daughter) But my Literal Minded moment aside, women have their own agency. Women have their own stories, their own passions, and fundamentally, they deserve better than just being tied down by someone else's problems, especially one who's done nothing but hurt them. (Yes, this is a problem with every Kylo-related ship I've consulted fan works for, but Reylo seems to have it at the forefront)
There's been backlash against that as well. One Twitter comment said that men don't want to be better because women refuse to bend over backwards for them. How insulting, and how degrading, for men! There are men out there who are genuinely monstrous, or at least on the loser end of the spectrum -- a woman's love is not going to save them from being monstrous. And there are men who are genuinely noble and kind, and don't need a woman holding their hands and giving all of herself to him in order to be that way; it's all them. The question is, of course -- why is this perspective considered anti-feminist, the idea that men can be better than they are and that women deserve better, that trans and non-binary people exist, etc.? Why is this perspective considered alt-right, other than the idea that certain militant Reylos are threatened by women who think independently?
In the end, these militant Reylos are the ones who think not only negatively of women (for obvious reasons), but to a subtle extent, men too. Well, not so subtle sometimes -- they actively put down men who aren't Adam Driver (a.k.a. someone to lust over). They think that men can't be better than they are without help; how insulting and in a way misandrist to even say! I doubt I can figure out what's wrong with these kinds of Reylos.
Regarding Darkpilot, it's not a perfect ship -- as much as I love it, I will admit that. However, I do love the potential between them, for what could have been -- something that Disney and Lucasfilm shamefully passed on. It didn't necessarily have to be romantic or sexual; it could have been platonic, or they could have even been enemies. But leaving mysteries unsolved, such as Poe recognizing Kylo on Crait...even if you don't ship the ship, you can't deny it's bad writing to leave it unsolved.