One advantage of linking a YouTube video in an aggregator setting is if the video goes viral, everyone is spamming Google’s server for delivery instead of hammering smaller services. Video is pretty expensive, so for now I see no issue abusing YouTube (assuming everyone here is already ad-blocking & DNS sinking anyhow).
Peertube uses the torrent protocol to distribute the load among active viewers.
I found a $15/mo server with unlimited (10Gbps) bandwidth for my personal instance. It would only become expensive if were to open it up for public registrations and use a lot of cloud storage space. Anything I upload can theoretically be viewed a billion times at no extra cost.
That’s still a lot of monthly money for a lot of folks which hurts accessibility for many, not all. The fact that we can’t agree on codecs throws yet another wrench in things as you need multiple resolutions & formats. I’m happy it exists tho & uses distributed serving.
In my case, I was already paying for this VPS to host other services, so the cost of adding peertube was essentially nothing. The server has enough storage and bandwidth to support dozens of users and hundreds videos, so the cost per person would be pretty low.
There’s a cost to doing the (re)encoding & storing multiple version of video. It’s relatively not more data to send one codec versus another, but storage & processing aren’t free either (especially with AV1 requiring hardware encoding unless you want to grind forever on a file).