Nostr has many bootstrap relays, the famous purplepag.es is competely unnecessary, not a single point of failure. From any relay through the data you can find many other relays, and from there the relay lists of anybody you want. It is a self healing network too.
Nostr provides signed, multi-endpoint relay lists. DHT relies on trusting third-party nodes for routing and data storaget serve your records.
Nostr's protocol and apps are already open.
I'm not saying pkarr is different than you imagine. I'm saying nostr is different than you imagine. And that they have similar levels of censorability.
Game isn't over.