With true E2E encryption, could you support features like recording a video and making it available for download? If yes, does that reflect how their video recording features work now?
No, thanks.
However, I think the real value of mitm is more to do with redistribution of streams and muxing to reducing total bandwidth over that required by a full e2e encrypted p2p mesh. I.e one upload vs one per peer (although this could also be done with e2e encryption with multiple recipients and simply routing through the service) and potentially a single download too (depending on how the muxing is done), rather than one per peer (but this couldn’t be done with e2e encryption).
Then the other client can download the video via the same e2e tunnel.