Because by design free/libre software respects our fundamental freedoms, and guarantees them by <a target="_blank" rel="noopener noreferrer" href="https://github.com/Chocobozzz/PeerTube/blob/develop/LICENSE">a license</a>, so a legally enforceable contract.
Before this peer-to-peer broadcast, successful videographers (or videos that make the buzz) were doomed to be hosted by a web giant whose infrastructure can handle millions of simultaneous views... Or to pay for a very expensive independent video host so that it can hold the load.