> you are "buying" nothing more than a URL in a JSON file (i.e. no legal ownership of anything),
This is wrong. I can see why you think it, but it is wrong.
The URL in the JSON file is free, as is the artwork that it points to. It's very hard to restrict the copying of digital artworks anyway, so why bother trying to?
The person buying the NFT is not "buying a URL". This phrase doesn't even mean anything! What they are buying is control of a record on the blockchain, which (with some slight hand-waving) contains a list of the signatures of the previous owners, including the original creator or their agent. While it is trivial to copy a JPEG, it is not at all trivial to copy the list of signatures from one part of a blockchain to another, unless you happen to have the private keys of all of the previous owners.
As such, the JPEG is abundant but the record is scarce. This mirrors the physical world, in which Picasso prints are abundant but signed originals are rare and hard to copy. What you're paying for is the uniqueness of the signature, not the ability to look at the content of the artwork, which you can probably already do for free on the internet.
"No legal ownership of anything" is not really true. You do legally own the blockchain record! You can decide whether to sell it or keep it, and you can generally dispose of it as you would with any other property. You don't legally own the copyright of the artwork, but as we've already established, that copyright probably isn't worth very much.
Your other statements may be perfectly accurate - I can't imagine 20M artists on OpenSea all turning a profit, and I imagine that a lot of the investors are likely to lose some money too. I just don't think that this has anything to do with faulty assumptions about how NFTs work.
No you don't. In fact, I don't think NFT ownership has been litigated in any court of law (yet). The deed/title analogy is pretty good. But what makes a deed a deed is that it has the force of the law behind it. NFTs do not.
This might depend on your jurisdiction, but in general legal systems are quite lazy: if it walks like a duck and quacks like a duck, it's a duck. If it's something that I have exclusive control over, and I paid someone else money for that exclusive control, then it's my property. There doesn't need to be a written contract or a deed, any more than there needs to be a written contract or a deed for me to sell you, say, my bicycle. If I agree to accept payment, and you provide payment and I provide you with the bicycle, there is no sense in which you are not now the owner of the bicycle.
The crypto space does have an unfortunate history with a kind of legal mysticism, in which people ignore legal practice in favour of attempts to re-derive everything from half-remembered Locke, or something from Nick Szabo's blog, or some weird way of doing things that turns out to be an elaborate attempt to evade securities law rather than any actual legal requirement for sale of property. The term "smart contract" takes this tendency and multiplies it. Ignore this stuff and focus on simple principles: party A paid party B for something that party A was indeed able to transfer to party B in return for the agreed payment. Unless there was an agreement specifying otherwise, B has just acquired some property from A.
So, what we have is the artwork. The artwork, as a digital artifact, continues to exist as long as there is a copy of it anywhere. A copy that was hosted at a particular URL may cease to exist, though.
"Buying a URL" doesn't make sense because there's no transfer of rights. I already have the URL! There's no meaningful mechanism by which I can take control of the URL, and there are no rights over the URL that anyone can sell to me. The reason people mock the idea of "buying a URL" is because they rightly observe that it doesn't make sense.
The value of the record is not directly related to the URL. The value of the record is that it has the artist's signature on it (or the signature of someone I believe to be the artist, or the artist's designated agent; fraud is definitely possible here!). Notably, the URL does not have the artist's signature on it (how could it? This also does not make sense as an idea). The artwork pointed to by the URL might or might not have the artist's signature on it, but if it does then the signature is easily copyable, because the image itself is easily copyable.
The thing that is not easily copyable is the blockchain record. This is because it contains an encrypted transaction signed by the artist's key, and I can't make a duplicate of this unless I have the artist's private key.
If I'm buying an NFT, I'm doing it because I think the artwork is going to be popular or important in some way. If this is true, there are going to be many copies of it. I don't really care about what happens to any single copy, even if it's the copy that was presented as the reference copy at the time I bought the NFT. If I'm truly concerned that the image might disappear entirely, I will download a copy to my laptop and save some backups. If it turns out that the thing I bought was so unpopular and unimportant that months later nobody anywhere saved a copy of it, then I suppose that sucks for me.
This is wrong. I can see why you think it, but it is wrong.
The URL in the JSON file is free, as is the artwork that it points to. It's very hard to restrict the copying of digital artworks anyway, so why bother trying to?
The person buying the NFT is not "buying a URL". This phrase doesn't even mean anything! What they are buying is control of a record on the blockchain, which (with some slight hand-waving) contains a list of the signatures of the previous owners, including the original creator or their agent. While it is trivial to copy a JPEG, it is not at all trivial to copy the list of signatures from one part of a blockchain to another, unless you happen to have the private keys of all of the previous owners.
As such, the JPEG is abundant but the record is scarce. This mirrors the physical world, in which Picasso prints are abundant but signed originals are rare and hard to copy. What you're paying for is the uniqueness of the signature, not the ability to look at the content of the artwork, which you can probably already do for free on the internet.
"No legal ownership of anything" is not really true. You do legally own the blockchain record! You can decide whether to sell it or keep it, and you can generally dispose of it as you would with any other property. You don't legally own the copyright of the artwork, but as we've already established, that copyright probably isn't worth very much.
Your other statements may be perfectly accurate - I can't imagine 20M artists on OpenSea all turning a profit, and I imagine that a lot of the investors are likely to lose some money too. I just don't think that this has anything to do with faulty assumptions about how NFTs work.