@futurebird As I understand it, PeerTube is designed to get around this by being a peer-to-peer network of servers.
Say you upload a copy of your ant video on server A.
It's really popular! 100,000 people watch it!
With PeerTube, let's suppose 25,000 of those people have an account on server B. Another 25,000 are on server C. Another 25,000 on server D. And another 25,000 on server E.
Server A needs to send the video once to server B, once to server C, once to server D, and once to server E.
It's then up to those servers and their respective users as to how to cover the bandwidth costs.
At scale, perhaps one could be ad-based, one is paid, one is run by a university and subsidised through student fees (or funding), and one's run by donations.
Each to their needs, each by their means!
And yes, I know this is a gross oversimplification! But if you have a distributed server model, then one viral video doesn't necessarily mean excessive bandwidth costs for the server you upload it to.