Don't go into spoiler territory. People reading might wanna watch.
And it made complete sense. I don't know wtf you're talking about.
The lore from the very beginning is built on the feeling of unease in the society and that something is not right. They're being fed propaganda. As a people, they're genetically modified to create artificial behaviours and responses. Like the death feedback to stop murderers. So when you see that, literally everyone is gay, it raises a huge fucking question. Then you realize it's because they were made to be gay or even hypnotized into it. It's likely a regular part of their teenagehood. You can guess why. My own is that the government wants to avoid teenage pregnancy while not taking away their sexuality.
The last complaint you have is ridiculous. Squealer is completely tied up with the main plot. They're really one and the same and fit extremely well together. The manipulation on all levels (social, psychological, environmental, genetic), propaganda, etc. Squealer is the backlash to all of that. A fight against all the unholy changes they forced on others. He may be a war criminal, but he was right. They laughed at him, but he was a human. He's a tragic character and it's a beautiful story.
Top tier anime.