This is their way to stick their foot in the door. The true issue here is that unlike gay or lesbian, homosexual can not be easily undefined as of or relating to the same sex. Gay and lesbian are more cultural words so they can be manipulated. For some time now we've been driving the TQ+ crew crazy by using the exact terminology of homosexuality. They also dislike bisexual because it literally means both or 2 but they have been working with calling it 2 or more genders.

With homosexuality the word itself counters their narrative about genders and spectrums. Language also drives culture so as long as the word exists there will be a cultural understanding that gays are same sex attracted. If they can convince enough people that the word is offensive then everyone is forced into using nebulous and capricious gender based terminology which no one really understands.

It's the primary thing which TQ+ has been very good at. Manipulating language into a postmodern shit swamp to garner support and sympathy of the general public.