But those other things is stuff which askes a sacrifice of you personally, while someone else’s sexual orientation only needs you pointing at them. In the Netherlands where I live it’s a lot less about sexual orientation (but still some), and a lot more about foreigners, be it asylum seekers or people of Moroccan descent who’s grandparents were brought over in 1960’s because of labour shortages.
How I’ve learned it is, that cognitive dissonance arises when one of your beliefs or behaviours is challenged by new information. This can make you uncomfortable, and to alleviate that, people have coping mechanisms. It’s probably these coping mechanisms which cause other people to say you suffer from cognitive dissonance. There’s a quite good Wikipedia article on this imo.