Sorry, only read about half the thread.
The sort of discussion / ideas / terminology the OP is using (which it's easy to consider well-known rather than niche if one spends a lot of time around it) is not a usual way of talking on Mumsnet, so it may be a bit naive to expect a large number of reasonable and useful responses when people don't even know the vocab, let alone find this a usual or predictable sort of question.
I think RachelWatts and RitaCrudgington made excellent responses.
Girls at my school were homophobic - even spending a lot of time with one best friend often led to rumours that the people were lesbian, and there was a general climate that it was definitely 'not normal' and something to be shunned / be afraid of. A number of classmates later turned out to be lesbian or bi (found out when everyone joined Facebook).
Things sound quite different these days, the impression I get re older kids is that most teens, other than those from some very religious backgrounds, are pretty relaxed about LGBTetc peers these days. But if a kid feels unable to come out, or is constantly paranoid that others will realise they're LGBT, then the perspective of a straight person who's okay with it might help. It definitely would have when I was at school, to teach the kids who were 100% sure they were straight that there was nothing to be afraid of, that gay people aren't going to jump them or something.
However, I'd guess a lot of the kids who would still be scared about being LGBT won't be from lefty white middle class families and so the perspective of another liberal white adult being okay with gayness isn't as useful, because that's everywhere in the media now.
In the end though, I think it's about personal boundaries, and there are occasions when people we know get jobs we might not think they're the best person for - but just need to let go as there's nothing we can do, it doesn't directly affect us and it might well be alright for those it does.