Sure, but storage is costly.
We don't know yet how long we can expect Nostr notes to last. I have some Nostr notes that are 1.5 years but for all I know they could be deleted tomorrow.
Discussion
My entire 1.5 year history is a 350mb file, around 17000 notes, not that much data really. If you're concerned about losing notes run a backup relay. There's options for umbrel, start 9, Citrine on Android, I think even one for old windows.
Absolutely. But for relays relaying a ton of users I have to expect that my notes may not persist indefinitely.
Yes, for users that worry about theit notes being deleted, running their own relay is a solution.
I responded to claims that notes are persistent. They might be, we don't know that yet.