We have had an analogue of NFT's for 100's of years. Title deeds for land and buildings. The correspondence is pretty good. In most places in the world title deed fraud is roughly a yearly occurrence. It typically happens like this: some poor sod goes on overseas holiday for a year or two. Some fraudster notices, and somehow convinces the title's office they own the dead. The banks, lawyers and everybody else accepts that as proof of ownership, so they are able to see the house and pocket the money. When our victim returns to discover someone else in their house, and find out why, they attempt to sue someone. That's when they discover the governments generally make the titles office "all care and no responsibility", ie the can't be sued. So they've lost everything, with no recourse. Here is one example: https://www.businessinsider.com.au/gazumped-how-criminals-ar...

So the title deed is absolutely a proof of ownership. The congruence actually goes deeper - saleable land is created when the government creates a title deed for it at the titles office, and what the title office really does is just record the transitions of ownership. Sounds remarkably like a bitcoin, doesn't it? Sadly it proving you own a title deed isn't done anywhere near as securely as proof of ownership of a bitcoin is done, or indeed proof of ownership of an NFT. Because of that I think we can safely say one day in the distant future, title deeds will become NFT's. It will happen in the future because as they say in physics, progress happens one death at a time.

NFT's just extend the title deed concept to other things. It is much easier to conduct commerce when you don't have to bring the car or cow to the auction, just a bag of bits you can cryptographically prove you own it. To think of it another way, we already do NFT like exchanges of commodities such as pork bellies. No one actually sees the pork belly. In fact if you are dealing in futures, the pork belly doesn't even exist. But nonetheless, we create pieces of paper asserting they exist, or will exist, and trade them. Turns out futures are very useful to farmers and the like, giving them some certainty over the price they will get their crop - before it exists. But once you realise we happily trade prices of paper now that assert ownership over things that literally don't exist yet, you will probably understand the proof of ownership thing he is getting worked up about isn't the huge problem he thinks it is.

This ease of trading mostly only existed for commodities. The vast bulk of things we trade aren’t commodities. NFT have brought the frictionless commerce we associated with commodities to whole new classes of goods. Before NFT’s, turning something into a commodity that can be traded required an enormous amount of YAK shaving. You had to define precisely what it was, ensure there was already a large market, create the trading platform - for all I know it might even have required an act of parliament. Now anybody can attach a bag of bits to anything, and it's actually easier and cheaper to trade than a futures contract.

It’s true they did that by making the proof of ownership thing not their problem. The NFT's solve the crypto and trading side, only. Proving and accepting ownership is left as an exercise to be solved by the buyer and seller. But it's not the show stopper problem he makes out. Really, it isn't.