>”passive neutral response”
This is the correct way to react in public to the troon. Do not speak to them. Do not look at them. Do not react to them in any way. Practice your neutral expression in the mirror, and if you are a social person also develop a thousand-yard stare that you can use in the event a troon engages you. The effect you want is as if you are looking straight through them as if they are not filling the space in front of you. If you can disengage safely and without fucking up your plans, do so, and when you do so do not say anything. Do not do anything. Do not do much as make eye contact or breathe in their direction. They do not exist. Dehumanizing them in this way opens the door to zero reprisal. No matter who they complain to, what are they going to say? “This person is aggressively ignoring me”?
If you must interact with one in a professional capacity, do your best to pretend they are a cop who’s pulled you over for a traffic stop, or like you are being questioned in court. You say as little as possible and give only the information requested. If they ask “do you know what time it is?”, you don’t give them the time. You say yes or no. Do not editorialize or explain anything not directly necessary. End the interaction as quickly as possible. You must ice these people out at every opportunity.