|Orientations are a dime-a-dozen. There are many different orientations, like the orientation to bully or to steal or to be a drug user or alcoholic, etc., etc. To single out sexual orientations for protection, while ignoring or discriminating against all the other orientations, is patently unfair and wrong. (We are not talking about behavior here, just orientations.)
Besides that, pedophilia is a sexual orientation. Do we really want to protect adults who have sex with little kids? Zoophilia is a sexual orientation. Do we really want to protect people who have "intimate relations" with animals? Necrophilia is another sexual orientation. But you get the picture.
The fact is, nobody discriminates because of sexual orientation anyway. Even if I tell you what my orientation is, you still don't know (I could be lying) because you can't see an orientation. Now, if I behave a certain way, say sexually or by crossdressing, then you can possibly figure out my orientation.
Truth is, it is certain behaviors that bother people, that cause people to punish someone or not hire someone. For example, we'll punish someone for actually stealing but not for just having the orientation to steal. We'll punish someone for bullying others but not for just having the orientation to bully.
So, for all those reasons, we can conclude that protecting only sexual orientations clearly makes no sense and is discriminatory to boot. It's flat-out wrong.
When people protect sexual orientations they are really trying to protect sexual behaviors but they can't admit that. They can't admit that because behavior is normally voluntary, whereas age and race and maleness and femaleness are passive states of being. We do not choose our age and race and gender--they just happen to us.
So, in any anti-discrimination policy or law which protects people because of their age or race or gender, adding "sexual behavior" to the list of protected things is unjustifiable. We would either have to also list a zillion other behaviors for protection or single out sexual behaviors for protection and discriminate against all other behaviors. And that's wrong.
In sum, anti-discrimination measures protect passive states of being (and also protect matters of thought or belief, like religious or political beliefs). Singling out either sexual behaviors or sexual orientations for protection in those measures is unfair, discriminatory, unreasonable, and wrong. It should be illegal to do so.