No sorry. I'm mainly just being a pedant. The point is that biological essentialism is almost never an appropriate explanation. Though it is often an expedient one for political purposes. It's far easier to pretend that sexuality and gendered behavior are inborn and thus not subject to choice than it is to understand that we are the sum of countless biochemical processes contextualized by our own individual life into a poorly understood conscious 'I' that can't simply choose to change its nature at a whim. It's just not, strictly, true. But if it helps to think about it that way it's not entirely wrong and I could just keep my mouth shut.
It's really similar to how HDL and LDL are not in fact any kind of sterol yet everyone will persist in calling them 'good' and 'bad' cholesterol. It's not true, but it's easier to understand than the truth and also will lead to similar decisions as knowing the truth.
I had a fairly long, elaborate post written, but upon reading it, I realized that it was rambling and didn't really get to a point... and the way I was stating things could be badly misinterpreted. =>_<=
I'll just point out that suggesting that choice has no role in sexuality* is just as misguided as saying that you can simply choose to be gay, straight, etc. Some of it is wiring (biochemistry), but some of it is
choice. It's just not one single choice, but a tightly woven array of past choices, not easily undone.
For a (safe-ish) example, there are women out there who like the aesthetic appeal of the female body, but identify as heterosexual, because the choices they've made have turned them away from considering other women as sexual partners. The right circumstances could
put such a woman in a position to actively make that consideration, and decide to act on it, either for themselves or for the pleasure of a chosen partner.
Which just goes back to what several people have already said - that the dichotomy of straight/gay is only useful for basic discussion, and is a false dichotomy when talking more broadly.
* And I know that you're not saying that, Alice, but it seemed a point that needed to be made, and is often disregarded, either implicitly or explicitly, in discussions about sexuality and choice.