If uality and GID are unrelated, why did people like Karl Ulrcihs and Edward Carpenter do this?

There are obvious similarities between the two (being gay and being female), especially when you take into account that, in the genesis of the gay identity, there weren't many out gays, so people just thought that only women were attracted to men, and vice-versa. Therefore, with that intuitive, emotional umption, if you liked men, you had to be a woman. When more gay men came out, the umption became less grounded - if so many men liked men, then how could liking men be solely a female thing?, so people eventually abandoned it, causing the line of reasoning to fall apart.