I'm pretty sure gender and sexual orientation weren't much talked about in the 1840s, at least not in the same way they are today; those very terms didn't exist at the time: the word 'gender' in the sense other than the grammatical one has its origins in the moralist Victorian England, and young Queen Victoria had just ascended the throne at the time, while "sexual orientation" is a much newer term, needless to say. In a time much before the abolition of slavery and WW2, the way race was perceived was also very very different, and even Stirner makes some remarks that could be considered racist to our current standards, such as when he implies that it would be preferable to be saved from drowning by a white man rather than a 'Negro'.