Comment by jacoblambda

that's all a choice of the streamer. some streamers choose to have TTS (text to speech) but a lot don't. Twitch is bad about TTS in particular but it's far less common on the youtube side of streaming.

Doubly so the twitch chat is going to mirror the streamer. So if the streamer is being a goon and playing up the twitch culture, you'll get twitch chat. But you can also have a very different chat experience if you establish from the get go that chat is to behave a specific way.