Looking back at TT, HH said
HH given your experience in EDI including work on hate crime, given your background,
and I wonder if that was a nudge nudge wink wink we all know you're a lesbian, and lesbians should be supportive of their trans 'siblings', LGBTQ+++ and all that...
CA may have been annoyed rather than offended, that HH seemed to bring up her sexuality like that to score a point.
Not that CA was hiding the fact that she's lesbian, just that she isn't giving evidence as a lesbian, and HH may have mentioned/implied that aspect of CA in order to make a point, namely that CA was trivialising the experience of lesbians and gays though gay herself - and possibly case aspersions on CA's objectivity, because the L is is not very welcome in the LGBTQA+++++ 'community'
It was after this accusation of trivialising that CA said
CA - As a lesbian myself I do not trivialise this.
That's forcing her to say something personal, when up to now she has been dealing in facts.
I'd be ...perhaps not offended, but unsettled/upset that somebody had said something that referred to my sexuality in a context where it was not relevant.
That's just my personal speculation on what HH said and how CA may have reacted.