Sounds like he just has brainrot then, and no amount of factual evidence could persuade him otherwise. Whether someone is "visible" or "has rights" isn't even the discussion. There are clearly harsh inequities between straight cis people and LGBTQIA people, just as there are harsh inequities between men and women.

It's like trying to persuade someone that we need oxygen to survive, and having them respond by saying they don't believe in the existence of oxygen. You can't really have a discussion with such a person. Personally, I'd rather be lonely than be friends with someone as exhausting as that.