Some viewers prefer livestreaming, and we see streamers catering to those audiences. It depends on the streamer, but often times there is much stronger sense of community when there is a live, topic-oriented chat, especially when the streamer engages with the chat. This is not something you can satisfactorily replicate with prerecorded streams.

Streaming is also much more low-cost to produce, editing can often represent an unwanted source of complexity and loss of creative control.