Criticism of the matrix protocol: https://hackea.org/notas/matrix.html.

I will not access the posted video as it's hosted on hostile infrastructure. I request that the author share their videos in a way that honours freedom. Continuing to use the current provider is to enforce the existing monopoly on video distribution and is counter productive to libre software. I will list some viable alternatives: Mediagoblin: https://mediagoblin.org/; Peertube: https://joinpeertube.org/; or via BitTorrent: https://en.wikipedia.org/wiki/BitTorrent.

I will not use the matrix protocol due to its origin with Israel's intelligence community. Its design is nonsensical in the contexts of liberty, privacy and cryptography. However the design is strikingly coherent if the goal was to design an encrypted communication protocol that was 'decentralised', but still auditable by external agents. This design is why government agencies would consider its adoption, but knowing its origins I can not endorse it.