In practice, you end up relaying a lot of traffic through TURN servers due to NAT issues, plus most enterprise-grade platforms connect to conferences as peers f

In practice, you end up relaying a lot of traffic through TURN servers due to NAT issues, plus most enterprise-grade platforms connect to conferences as peers for recording purposes, and allow for server-sourced multicast for things like presentations with large audiences, or to allow synchronized video without lag or quality issues.