There is no indication that there's a time when an English speaking person becomes English speaking.
Sure there is - their first word. My first word was "hot." I had touched a stove and burned myself. (Not a bright kid, really.)
Yet if, at the time of that first word, you were adopted by Chinese parents, taken to China, and brought up where only Chinese was spoken, you would likely have turned out to be a Chinese speaker and not an English speaker.
But here's the thing. While you have to have spoken English at some point to be considered a speaker of English, we regularly ascribe sexual preferences to persons who have never had sex; to persons who are not even sufficiently physically developed to be capable of sexual intercourse.
However, we don't do this arbitrarily. Presumably we base it on observed behavior.
Now, there's no known convergencies in the environmental histories of gay persons at that early age that would explain why they're gay.
That this is unknown does not prove that there is no environmental involvement.
And I'm supposed to take seriously the idea that "we don't know that people are born gay"? C'mon, already. There's more than enough data for us to come to a tentative conclusion. Unless you're already ideologically committed to the idea that our sexual preferences are entirely a matter of choice, not heredity.
You appear to be saying that on the basis of a false dichotomy. Sexual preference might be neither hereditary nor a matter of choice, much as a person's native language is neither genetic, nor a matter of that person's choice.
There was an extensive discussion in
Focus on the Family Will Keep your Kid from Being Gay and in
Determining genetic influence on sexuality. On my reading, the evidence pointed to genetics perhaps biasing the sexuality but not determining it.
I won't comment on the rest of your post, except to say that it is mostly a rant.