Not that it matters as all discrimination is wrong, but DS is not flamboyant either, he is just a very tall, stalky self-conscious teen so all this mocking has made him very insecure about his identity whatever his sexual orientation may be.
It’s a difficult age, especially boys, they seem to jostle for position. We had a few repeated incidents of homophobia but thankfully school had been called out by Ofsted for being weak and as such came down on the perpetrator quite hard.
School communicated to us exactly what had happened, exactly what they would do and exactly what DS should do if it happens again. Kid was suspended.
That said, it didn’t put an end to them bullying, they moved onto other children. However, one of those children didn’t like that so much and lamped him. Which, if I’m being honest seems to be the better way it gets sorted at secondary. (Jostling for position)
But what I would say is we did a lot of work at home about acceptance, tolerance, LGBTQ+ history and standing up for what you believe in even if it’s hard. We made sure that one bigot wasn’t going to define who he is, was or decides to be. And that actually really helped grow some confidence - which as a teen is generally what you need.