system
Given the following post, respond as if you're commenting on Reddit:
human
CMV Chihuahuas are ugly & have shitty personalities.

Chihuahuas are a nuesence breed & idk why they're so popular. Going to the dog park, all the other dogs are chillin, playing, or sniffing. Not these little terrors. Their constant high-pitched chirp barks are piercing. And they're constant. They don't let up.

Chihuahuas are ugly and they have shitty personalities. Why would anyone ever do that to themselves, and their neighbors? Why do they exist? They look like large rodents.

When you love your dog, you put up with their annoying traits. But chihuahuas are objectively over aggressive. I wish they'd go live in their own separate community. Or at least have their own separate dog park away from the other dogs. They can go nuts shrieking in each other's faces all the live long day while the rest of us enjoy the weekend.

Edit:
To clarify, I don't like feeling vehemence towards these dogs or their owners so I wish I didn't have this view. I thought maybe some people would point out their better attributes & actually help me see them in a better light. Instead of resenting them & wanting them to go extinct

Edit:
There have been some really good points made here. I apologize if I didn't spend much time on anecdotes, although I'm touched by how much of you love your dogs. And you've shown me some undeniably cute chihuahuas, the long haired ones, and although they still have bug eyes, they were pretty darn attractive I cannot deny. And your stories about how well behaved, fun, and funny your chihuahuas are. All very cool. It makes me conclude "not all chihuahuas" are a pest to be exterminated; that your very special little guy or girl won the shit-bred lottery.

But a lot of comments only gave supporting reasons for why they are the way they are; greedy & unethical breeders and negligent owners. Chihuahuas lost the genetic lottery. Their defects cause their anxiety & aggression, and lots of owners don't care for them properly so you have the stereotypical "demon ankle biters" (if I may steal that term from one of you). I guess I don't dislike the breed any less, but I have been inspired to add some compassion & empathy along with my hatred. I can have both. And also, I now also hate greedy breeders & bad owners.

I still have to stay away from them at the dog park & have restraint when my niece brings her "dutchess" over; who's bark is like a thousands sparos piercing your brain (god forbid someone across the street sneezes). But I think I'm the problem. My hatred is not going anywhere, unfortunately. But I enjoyed discussion & insights. Oh, and also, fuck puppy mills.
gpt
So, first genetics play a huge part in a dog's temperament. It's why labs are generally chill AF and Malinois are crackheaded working dogs. It's also why Chihuahuas are crackheaded demon ankle-biters for the most part. The breed is known for being high drive/energy and protective of their people. Sadly for them, it's wrapped up in a cute 5lb body that most people treat as if it's a barbie doll that needs the same mental and physical stimulation of one as well. So you have the typical lack of training/exercise/mental stimulation feeding into the problem. 

The other side is that they are, by far, one of the most poorly backyard bred dogs out there and it's extremely hard to find one from a breeder that actually cares about the future of the breed and not just creating more "teacup" monsters. Most backyard bred ones are not health tested(meaning hip, elbows, and eyes are tested for faults and stored in a data base as well as genetic issues being ruled out) and are not breeding for a sane mind. So you have a lot of dogs that are bred from insecure, high anxiety parents and then put into homes with people that don't realize they have a high energy dog that needs both mental and physical stimulation and a good therapist. If you can find a decently bred one that the original breeder focused on a SANE mind along with the Chihuahua attitude, you would find they are still stubborn but also very smart and very quick on the uptake. Once you add a good owner to the mix, you have a very amazing little dog that definitely deserves NOT to go extinct. A good demonstration would be Ludvig, the IPO Chihuahua or the Chihuahua obedience class.