That's why when referring to the price people generally don't talk about sales, but about the "floor price", that is, actual committed listings that someone is willing to sell for.

The floor price can be a dubious measure of value for many NFTs, since there are few buyers, but for highly liquid collections like the Penguins, there are corresponding standing "offers" that owners can sell into any time they want, therefore creating a spread between listings and bids.

The price is (was) real.