It's all there is to NFTs. What you're describing are systems outside of NFTs. It's similar to saying there's "more to this excel spreadsheet" because the company uses it as a ledger for all their accounting. When it comes to buying a house or a skateboard, you have a physical house or skateboard. You also likely did due diligence beforehand for the house, like having somebody look over the actual papers registered with the government to make sure the sale is legit, actually seeing the house, etc. The Blockchain part is completely invisible in those cases.

But in this analogy, some people really do pay money just to have their name added to the spreadsheet. No house, no skateboard, just their name added to the ledger and a digital image that the ledger now says they own. But the thing about digital property ownership is in an actual sale of, for example, music rights, there is a governing body that enforces your ownership. No such thing for the NFT images people have been "buying". And buying is in quotes because it's crypto, there are no official receipts.