Well… that’s the “Gateway to the old world” use case in the article – https://bloggeek.me/webrtc-conferences-mix-or-route-audio/#h-gateway-to-the-old-world

Here’s the thing – you can’t have nice things if you are adamant to use the old and stale.

To get the benefits of an SFU in teleconferencing, you have to let go of the “tele” part of it, and only attach it as a last resort thing for those who want their old and stale. It shifts the focus and the mindset and can be a risky proposition – just until the point that it becomes commonplace and takes over the old crap that was used by the industry.