It is a behavior. But homosexuals cannot be a protected class on the basis of behavior.
It his to be as genetic as the racial or sexual assignment of a person. And they have been looking hard to find that genetic tag, but have not found one.
Because there isn’t one. And that is devastating to them.
It would be interesting if they did. If a genetic marker were to be found, the docs could screen for it. Some parents, probably many parents, would consider homosexuality a defect, or at least a serious psychiatric disorder that their child would have to carry for life. Some of these parents, possibly many of them, would opt for abortion, and then try again for a normal kid. What would the left do? Suddenly discover, for the first time, a reason to limit the abortion license? Which would prevail: a woman's right to choose, or the sanctity of homosexuality?