We already have a concept of ‘ownership’ in the real world.
If an artist wants to sell a digital work to someone they can do so - just write up a contract, sign it, exchange some value, and you’re done. Selling things is a well understood concept. We have a legal framework for it.
If an NFT represents a transferable sellable set of rights, then those rights have to be expressed in a sale agreement of some sort (implied or explicit).
Sure, the blockchain gives you an easy way to handle the ‘transfer of ownership’ portion of a subsequent sale, but items not some radical new form of ownership - it rests on an underlying legal framework that is indistinguishable from selling deeds to acres on the moon or selling numbered prints of an artwork with a certificate of authenticity.
If that "socially recognized ledger of ownership" ceases to exist, then what?
We can hardly rebuild stuff from source after 20years time, so I'm pretty sure you will not be able to revive long dead blockchains as easy as renting a space to trade physical objects of collectible value.
The physical equivalent is a worthless painting that no one cares about and your grandchildren throw out.