It isn't semantics. We give protected classes extra protections because they are attributes of who a person is. To give the same protections to actions that people do would be wildly different.
A salesperson should be able to be fired for shit-talking their own product. A customer service representative should be able to be fired for treating a customer inappropriately. The editor of a magazine should be allowed to edit contributors' articles. Putting speech on the same level as a protected class is ridiculous.
Courts aren’t machines that evaluate a series of IF statement in vacuums; they look at the entirety of the situation. They’re going to be looking for the root cause of the reason that management has landed on their decision.
Someone mentioning they’re gay after being asked if they have a wife would be a very different situation from someone who, for instance, is engaging people in inappropriate and unwanted discussions of sexuality.
The law is quite simple: was the person fired because of their membership in a protected class?
A salesperson should be able to be fired for shit-talking their own product. A customer service representative should be able to be fired for treating a customer inappropriately. The editor of a magazine should be allowed to edit contributors' articles. Putting speech on the same level as a protected class is ridiculous.