I would say that if we can’t rely on cryptography, we’re basically SOL on all fronts.

But the way around that would be to focus more heavily on device / data ownership. The unfortunate thing about Nostr though is that there is no authentication required to spread data. It’s not locked to only the relays that you choose.

So keeping notes only on your own device isn’t an option either. The only way to be “safe” on Nostr is to hide in absolute obscurity and hope that nobody finds your pubkey who you didn’t want to find your pubkey lol