You need to understand that this is not about sexuality, but about patriarchy. For them sex is about power over women, not about pleasing them. Cunnilingus focuses on female pleasure, which is a problem for this world view. Men unwilling to take part in the oppression of women are seen as “unmanly”. This is expressed through the accusation of being “gay”.
The unfun part is when its your personal rights (personally) and you have to discuss them to defend yourself.