2) One of the things Nostr did get [slightly] wrong was the hashing of the JSON. It's pretty straight-forward to sort properties, and remove spaces, to create canonical JSON that can easily be hashed, but (and I forgot the specific reason) Nostr made it where you can't directly store Nostr in IPFS (for example) and have the post hash/ID be identical to the IPFS CID of the canonical JSON. They missed that opportunity because fiatjaf was not well enough versed in IPFS, so he got that a bit wrong.
All that being said I am still a fan of Nostr. It is far better than other Social Media protocols imo.