For the source code part git is already decentralized enough, it is not worth trying to censor a repo cloned on tens of thousands of machines locally.
For the social part: censorship resistance is important but it can be a curse, like with radicle which cannot possibly get a decent UX.
As we see with bitcoin, we can hopefully keep one of the most important system decentralized while syncing state every 10 mins.
Nostr trades off with the possibility of centralization around one or a handful of relays, but at the same time it is trivial to backup the already signed messages which are republished any time, anywhere.
Nostr is the practical solution to this problem in my opinion.
