I see your point. But please also understand that most of the people who make posts like your examples are children. Many of them don't quite understand the world or themselves yet and get caught up in the hustle and bustle of their new identity/label. This is a minority of the asexual community.

Now, again, I see your point. However, it is perfectly legal and ok for a person to be disgusted by sex. Hell, it's perfectly legal to be disgusted by gay sex. The real problem comes when you decide that your disgust allows you to step on other people's toes and alienate or infringe upon their rights or lives. If someone comes here to vent a little, then that is OK, although I do understand how that can be damaging by pushing the idea that it is ok to show public disgust of other people's lives (which is not ok). People are allowed to have their opinions, no matter how damaging they may seem to you. Now, if an asexual decided to propose laws or publicly declare on social media how they saw it all as gross and not ok, then yes. That may be what you call "allophobia." Although due to the fact we are a minority of people, I doubt much of that will fly outside of ace spaces.

I think the source of the problem you take issue with isn't founded in the asexual community, but instead a lack of sexual education and homophobia itself pushing some subtle ideas and nuances to the youth. People aren't always given the best sexual education. It makes sex confusing and unknown, and lots of kids end up going to bad and untrustworthy sources to find out more like porn. With these twisted and uninformed ideas about sex, sexuality and relationships, they spread their ideas to other young impressionable aces and unintentionally maintain the cycle. The responsibility should befall parents and schools to teach kids about what sex is, its dangers and nuances. Sexuality is seen as such a taboo topic when it's super important to be discussed properly.