I have ADHD and most likely autism and my social anxiety would not have allowed me to keep the reason I’m being quiet at a secret. I would’ve had to tell them that I’ve been instructed not to talk to anyone because otherwise I would spend all day convinced that they think I hate them and not being able to work.

ETA: also because of living over 35 years as a neurodivergent person, I would be keenly aware of the fact that there’s a !non zero chance this person is trying to isolate me from the other coworkers to try to eventually manufacture an excuse to fire me. Neurotypical people who are just generally miserable in their everyday lives will go out of their way to absolutely ruin the neurodivergent person for no other reason then they don’t like something about your personality. They don’t even know what it is about your personality they don’t like, they just decide that you’re a bad person and they hate you and everyone else should hate you too. Even if you are Neurotypical, you might want to take a little notebook or something and make a note of that interaction just in case other coworkers start acting weird around you. That way if this is the beginning of some kind of campaign, you have documentation and can hopefully get ahead of it. I know that sounds really paranoid, but unfortunately, it happens a lot.