Their business is joining meetings from 7 different platforms (Zoom, Meet, WebEx, etc.) and capturing the video.

They don't have control of the incoming video format.

They don't even have access to the incoming video data, because they're not using an API. They're joining the meeting using a real browser, and capturing the video.

Is it an ugly hack? Maybe. But it's also a pretty robust one, because they're not dependent on an API that might break or reverse-engineering a protocol that might change. They're a bit dependent on the frontend, but that changes rarely and it's super easy to adapt when it does change.