First person: Talking about oneself. I, me. Second person: talking about the listener. you, your. Third person: talking about someone who is not the speaker or listener. He/she/it/they Fourth person: Talking about total bullshit.
In this context, "Chat" is second-person plural, used by streamers to address the portion of their audience able to respond in the text chat that always accompanies these things. It does contrast with how a radio personality might address "listeners" because radio listeners don't usually have a method to respond in real time, so it's usually a rhetorical question; a streamer addressing the chat is asking for a response.
