I had successfully been running a rudimentary version of WP Livestream for my own church. The basic kinks seem to have been worked out.
Now I wanted to know if this was something other people would be interested in.
The easiest way for me to validate was to ask people in the same shoes as me - people running live streams at churches with WordPress sites.
I posted a request for 10 beta testers in a Facebook Group (WordPress for Churches). In exchange for beta testing they would get the plugin for free if/when I launched it publicly. I got about 70 comments.
One thing I should have done is instead pointed them to a landing page where I could have collected their emails.