I don't think so. Groups that want to chat go where community leadership determines they go. If people want to participate in the x twitch streamer's off-stream chat they are forced to go where that community decides to be. They do not have to follow an audience by going to discord, they make the audience go where they prefer. They don't get the audience from discord, discord gets the audience from them.

For this reason chat programs are uniquely vulnerable to people going elsewhere. They have no inherent audience of their own, they are not social networks, they are tools and they can be replaced by another tool at literally any moment. People will run discord and an alternative side by side until they can drop discord altogether. That's exactly how other chat tools died historically as well.