Interesting article (my French is not good, but with the help of translation I get the idea). Thank you for sharing.

Ahh so, I think there is room for confusion. Fediverse is “p2p” only in the context of the (federated) servers. PeerTube/Lemmy/Mastodon/etc. are still “centralized” in that your instance (e.g. programming.dev) is shared with many other users (possibly worldwide). This potentially increases the cost of delivery, because a user still has to find a server, and may select one that is ideologically, rather than physically, close to them. Because YouTube’s servers are ideologically homogeneous, there is no reason to find a server other than the one physically closest to you, and thus the cheapest to stream from. So delivery costs to the end user’s terminal should be even higher for PeerTube as compared to YouTube!

A completely flat, p2p architecture potentially eliminates almost all of the cost of delivery, but it does introduce other costs, and doesn’t eliminate the need for video encoding. I don’t have any research available, but I feel confident it will not be simple to compare with centralized services like Fediverse or traditional web services. I will keep my eye out for research.

There are many reasons to switch to Fediverse. I’m simply arguing that “efficiency” is not one of them :)