Meant to add this below:
"Your point about just adding ZS is well made. But it still requires them to know what ZS is, have an acc, know what Nostr is, and have an Nsec. Easy for us but actually many hurdles for newbies once you add them up."
To stream to nostr they should at least have heard about it or what's the point? Like mentioned below, a Twitch streamer wont have a manifest url for their stream so I wouldn't worry too much about that. The real question is how can we make nostr live events more popular and get them noticed OUTSIDE of nostr to attract more creators?