Peertube is federated. It seems to work similarly to Lemmy. I went on a random instance and clicked “discover” and noticed that I see videos from other instances. So at least the hosting cost is distributed across instances.
The other issue then is the bandwidth. Peertube uses p2p among viewers, so if there are many viewers at the same time they can take a significant load off from the server. Instances can also cache each other’s videos to split the bandwidth cost between them.
I think these design decisions means that it is possibly viable, though it is definitely way more expensive than non-video federated communities.
It depends on what your bottleneck is. For example on my system I get
$ systemd-analyze Startup finished in 11.976s (firmware) + 3.879s (loader) + 2.013s (kernel) + 157ms (initrd) + 6.354s (userspace) = 24.382s graphical.target reached after 6.316s in userspace.
The kernel boot process is only responsible for 2s of my boot time. So even if this does end up improving boot times, there’s very little it can do. The real improvement for me would be to choose a faster-booting m/b. You can run
systemd-analyze
on your setup to see if the kernel boot time is more significant for you.