Because deep inside themselves, they know they'd like to date and marry a transgender, but they can't bring themselves to admit it!

Pretty much this. But they will deny because reasons

First of all, is Spiderman "Pansexual" in any of the comics available?

If not, why would they make a movie like that? To please a minority?

Are there any gay comic heroes?

Reactionary threads, lack of debate framing.

Being from the south, I can attest that term cultural is more accurate than religious. 

This site is primarily a gaming site. If you let what the means sink in, you will understand that a majority of the people in gaming sites tend to argue nonstop about the same arguments and are thus starved and will jump to the nearest argument. Not saying that its everyone.

However, typically the original post is significantly more irrational than the commentators. A reference point would be yesterday when someone posted about a youtuber saying that people who only like Nintendo products are mentally damaged or something, and "expecting people to be civil". In other words, just unanimously agree. Which is insane.

To expect people to change their attitude to match what you or the majority desire, well after, what is clearly at least, many instances of them not changing, is insane. If you're willing to make a thread about people being crazy over their thoughts, you and you're thoughts just as crazy. Chances are, you're more crazy. Painting everyone else in a picture where they are crazy will never legitimately detract from the fact you're finger painting, dyed in the same color.

Simply put? Because most people feel uncomfortable with the issue and there´s lot of, let´s say, extremism in every front.

The way people deal with their sexuality (no matter if they´re homo or heterossexual or whatever) is something very, very particular of each person, and it is directly related to many aspects of the formation of its personality (cultural background, beliefs, fears, family relationships etc.) but many people don´t understand that. They think that sexuality can be resumed to a few concepts or "logical" ideas, but it can´t.  Sexuality is personal and its a complex issue, and but many people still insist in treating it as something small and public. Then the issues, discussions, arguments start. 

Corrected again. Remember that whites are not always in the majority.

Edit: And I may have to correct myself because it is possible to be in the majority and still have to face some sort of discrimination.

people empower words much too much

 Both are absolutely persecuted still. No need to fight over which minority is hated the most, because that's not the point. Nobody should be hated for sexuality or race. At all.