All I can tell you is decentralised solutions in general are needed because when centralised solutions fail us for any reason (repo too controversial, banned devs, hacks) alternatives have to be there instantly. This means we need to build these tools in advance, meaning right now. Building over nostr in particular adds the benefit of getting rid of walled gardens for good, and tapping into the global network that is forming currently on nostr. It's not so much about what has happened than it is about what cannot be allowed to happen (censorship, failing centralised solutions). When a centralisef solution fails, it fails big.