"There are so many reverse ships that I'm not sure of my interpretations anymore."
(Defined as the top/bottom of a pairing in same-sex ships being “reversed” when compared what the shipper likes. In Japan and other parts of Asia, ship names are often not considered to be interchangeable, as it denotes who is top (left) and bottom (right). Fandom folks in the east get very attached to their top/bottom preference for a specific ship and go to great lengths to avoid seeing their ideal flipped. This includes blocking and muting tags that may have reversed ships in the results, as well as blocking users who suggest a top/bottom be reversed.)
They're one of those mythological creatures that often pop up before the shippers of fixed pairings. Although these shippers are careful not to say it out loud, they actually tend to question the other faction's sense of taste: "Did you even see the original work? How the hell did you get to that? Do you need your vision checked?"
Yet, most people know that there's no point in protesting and that if there's something they don't like, they should just not look at it. So like you, they try and protect themselves by blocking works and muting keywords or even use tags and warnings to keep the reverse-pairing people away.
The way things work is through a bunch of secret agreements that came about naturally through history repeating itself. There is no law that says, "A person who fails to indicate his or her preferred pairing will be fined up to five grand and imprisoned for three years" or "Anyone who even remotely supports reverse pairings will be fined."
Sometimes, you order a canon pairing and you get something else. Like when you're at a simple restaurant and order bacon-wrapped asparagus, but they end up bringing you stir-fried asparagus with some chunks of bacon mixed in.
Because the ingredients are the same, this kind of accident often happens: you are looking for your OTP and end up experiencing close encounters of the reversed kind.
Think about the real world: how many different "Stranger A x Stranger B" pairings are out there? Most couples have nothing to do with you so you don't get to have a say about them. Still, if you spot a couple of strangers French kissing on the other side of the road as you frolic down the street, maybe in a really good mood and excited about seeing Demon Slayer: Infinity Train for the 178th time, wouldn't you find yourself thinking "Are you for real?!" and hope they get out of your sight ASAP?
I think this is a good analogy for being annoyed at the sight of reverse pairings, getting heartbroken at the sheer number of them, and then having your own worldview shaken to the core.
If there is no official answer, then we're just mass hallucinating
In other words, there is no such thing as a "correct answer" unless the official answer has been given.
Even if your OTP is canon, when you write a story that is not present in the original work, it means that it will be different from the original work.
If you wanted to write a "correct" story that is exactly the same as the original, you would have to copy the original and if that's the case, your creation would have no value whatsoever as fan fiction. I mean, at that point why not just read the original?
Let's start from the premise that fan work is all wrong. Wondering if your interpretations are mistaken in a world where everyone is wrong is like having a naked meet-up in front of the Hachiko Exit in Shibuya and begin to wonder whether your nipples have a weird shape.
What's weird was having a naked meet-up in front of Hachiko in the first place.
Fan work is not a contest of right and wrong, but a fantasy where half of the people wonder if they're hallucinating, and the other half reassures them that "hallucinating is so much fun!". The latter is winning.
If the large number of reverse pairings popping up recently is frustrating to you, your argument shouldn't be that they definitely clash with the story, but rather you should get into the swing of things by shoving more of your preferred pairings into your mind.
Take the obsession with being right and turn it into creativity
It's important to believe that your interpretation is the correct one, but don't try to get others to accept it, or to make it the official correct interpretation.
I mean, technically you could do that, but you would also have to pull a Misery and lock up the original author to force them to write whatever you like. That's madness.
Normally, such madness should be kept within the confines of one's own mind, but it can be released through creativity.
Furthermore, the fact that you can make people happy and call you "God" instead of "monster" or "criminal" by showing your insanity in the shape of creativity is what I call a miracle.
When you write a story about your OTP, doesn't it increase the number of total works about your OTP by one? That much is clear.
Asking someone to write more works about your OTP and hoping for reverse-pairing works to go away is just crazy.
Before all that, why don't you help make up a number?
If you do this, you may be able to bring light back into the eyes of the people who have been relentlessly searching for works about your OTP. Some people may even follow after you to keep up the momentum.
Whenever you feel sad because your OTP's fandom doesn't look too lively, remember that you have the power to breathe life into it yourself!