There are countless other examples where some new service gets a lot of funding and eventually dies. Most probably really was spent out without being pocketed, fancy office was rented, state of the art tech used, huge sallaries and ridiculous benefits etc.
I cannot imagine NFTs or crypto in general being widely used. Tech is inefficient and not solving anything better than what we already have been using for years. If someone wants to sell digital art there already are ways like DeviantArt, Patreon etc.