The difference in the ability of a developer to modify an open source software product (think: Gimp or Jitsi Meet) to suit their needs versus using a platform SDK that is designed to provide flexibility and to be used by devs is massive.

I spent some time looking at the Jitsi Meet source to confirm this assertion:

https://github.com/jitsi/jitsi-meet/

It was quite clear that trying to use that code to execute my use case above would have been a very large waste of time, and quite possibly (given the lack of docs) a futile exercise.