Royston, from your link, page 6 table A
Heterosexual infection in UK annually up to 2009 (2009 figure expected to increase)

Adjusted*** 240 330 490 600 740 830 870 1000 1130 490
       Observed 228 314 380 467 569 646 648 655 635 217
It shows a very low number of heterosexual infections and an increase of only a hundred or so per year.
A very rare disease among British heterosexuals and no sign of it approaching problem in the gay community.

I am not blaming or judging.

Thank you for reminding me what this discussion is about, but i am not part of it.
I came in when you said things that I believed to be false or misleading, and a couple of googles confirmed it.

A quarter of a century ago everyone assumed that AIDS would be indiscriminate here as in Africa.
You still think that but the WHO now thinks that is not likely.

There is uncertainty about why.
You and the WHO both suggest what the factors are, but theirs list is quite different to yours.
I give WHO more credence than you.