That's because the transphobic assholes who answered your question wanted to make sure they inflicted some damage.

What they should have explained is that some people at the extreme ends of the Kinsey scale are only attracted to some people at the extreme ends of the gender spectrum.

And if we could change our sexuality whenever it conflicts with our conscience, there'd be way less tragedies in the world.

It's a shitty situation all around, but if they date someone they aren't actually attracted to, just to reassure everyone else how open minded they are?

How is that at all fair to their partner, who's just going to wonder why things always seem so uncomfortable, and there's always an excuse to avoid sex.