Crypto Art NFT, please explain!

What makes this different from a registered serial number?

How is it ownership if you can’t remove it from the blockchain?

How is it ownership if there’s royalties on resale?

What about giving the item away? Like if I had a painting, I could just give it to someone.

What about anonymous sales?

Do you basically just own a piece of blockchain?

The whole thing seems like a scam.