> exactly like BitTorrent there will be neither punishment nor need for it if some clients disobey.
"Punishment" (tit-for-tat algorithm) is one of the defining features of bit torrent, especially in comparison to what came before it.
This is not a "punishment", and what clients to differs greatly.
The original spec for the original client allocated a portion of its bandwidth to random peers instead of known-good/preferred peers, so if you had no chunks you were basically bandwidth and/or peer restricted.
If you take the arch linux ISO right now and put it into aria2c to be a new, unknown client with no data to offer, you'll find that while it takes a few seconds to join the network, fetch metadata and connect to peers, you'll quickly saturate your connection completely without ever uploading a single byte.
If you wanted, a streaming network could use direct access or low-hop access as seeding incentive - seed to get slightly lower content latency. When the streaming client is controlled by the content provider, seeding is easily forced and topology could be controlled centrally.