Just my personal experience: I have never experienced a negative encounter with a trans person throughout my life. They were all cool, fun (or trying to be) and friendly. But two-three months ago, I accidentally asked a trans looking person behind the market's counter as simple as this: "how are you?". I was trying to pay for a chicken wrap. The person started screaming and shouting about the adverb "you" which I've used, insulted me and rang the garda. I was shocked and I wasn't able to react in any means. Sometimes I miss my native language: Turkish is gender neutral.