Jack Dorsey's first ever tweet sells for $2.9m

No, it didn't.

A digital trading card of the tweet was sold. He could have made 100 cards, but he made 1.

Regardless of the number, the actual tweet was not sold and is not owned by anyone in any meaningful way.

Similarly, there should be no headline saying that John Cleese "sold the Brooklyn Bridge" when his NFT is transferred to someone.