Whay does a person who is adopting a not standard gender and/or sexual preference choice have to 'come out' for it to be considered 'valid'?

people who have standard gender and/or sexual preference choices aren't expected to 'come out' and declare their position as a so called cis gendered and/or 'straight' entity.

Can i 'come out' as a straight man-by-dna male please? 8-) i don't know exactly what i would be 'coming out' of but heck iit sounds like fun.