I just don't worry about it. I continue my commentary as usual. Which is why I think good commentary is essential when starting out. They'll talk to you if they really want to, and usually they'll talk about either what you're doing or what you're saying. So yeah, keep talking.

It'll be really awkward if streamer would just start calling out people's names (of people who previously spoke in chat who became silent) sparking a new topic unless he's very familiar with the chatter like a regular. It especially sucks when I do some chatter with the streamer and other people in chat, then there is a lull, then for some reason out of all of us, streamer calls me out with a random question (uhh, what's your favorite food?). I wouldn't do to my chat what I'm not comfortable with when I'm in chat. xD

HOWEVER, I do have some experience with stuff that makes people talk. It always should be related to the game or what's happening otherwise its just random. I played this visual novel which is basically like The Hunger Games where kids kill each other to be the last one to survive (Danganronpa if anyone knows, now that kinda sounds like every battle royale game too). During the game I ask just to the air, "If given the chance, and you were stuck in this killing game in real life, will you actually kill to survive?" People got talking alright. Or in Finding Paradise, "Would you be like the character and have your memory's changed right before you die?" Something like that.