It's like if I gave you the opportunity to buy the words "The Empire State Building" written on a napkin with a promise to never write those words on any other napkin. You might buy that if, say, I was famous. That's an NFT. You're not the new owner of the Empire State building.
So the analogy would be that some third party took a copy of your photograph of the building and sold the rights to it despite them not having the ability to do so?
An NFT could include the rights to the actual art itself, but most likely youre buying a sole reproduction. Similar to how going and buying a copy of a photograph at the store doesnt necessarily give you the explicit right to reproduce it for profit. Copyright is different from possession. NFTs are possession, unless they spell out that the purchase also transfers the copyright.
[1] https://crsreports.congress.gov/product/pdf/IF/IF11478
In other words, the complaint is that when you curl e.g. https://images.opensea.com/some-pixel-artwork it returns a PNG of the pixel art without adequate license metadata, and there's no one to talk to that will fix the issue.