No I can't agree with that.
'It's up to him to define his sexuality. Not really'
I worked in HIV prevention in the 90s and it was always targeted at men who have sex with men (and idu) as if it was targeted at gay or bisexual men, it would miss men who did have sex with men but saw themselves as heterosexual.
'And sexuality does not = who you have sex with. Yes really.'
No not at all. In porn 'gay for pay' is a thing. The women who are with women may not be gay. Loads of people all over the world who are gay are in het relationships for a variety of reasons. There are gay people who are not sexually active, also straight people who are not sexually active. People experiment. Many kids know their sexuality before becoming sexually active.
The thing with all this is that the current push to totally redefine what these things mean eg a male and female identifying as a queer or gay couple etc is undermining the reasons these things were a bit flexible in the first place.
There are also a lot of conversations around enforced heterosexuality which feed into it all.
It's a real shame tbh.
The other reason might be that bi people are still viewed with suspicion by both straight and gay people.