Yeah, when you make an NFT you have what's a called a smart contract that's stored on the blockchain. The smart contract is what holds all the info for the NFT to function (ownership, what digital asset it links to, and any royalties to be paid)
So it doesn't matter if you trade the NFT through Peters marketplace or if you go through a second-hand one. It all has to refer back to that smart contract
It's important to know you're not trading a digital asset. You're trading a token that links to that digital asset. If the owner wanted to, he could make that digital asset defunct if you try to trade it with someone else.
Doesn't mean Peter isn't running a scam job because a rug will come. Although yes, you are correct. Most people here look at jpegs and think oh, overvalued NFT scam that I can copy with metadata and a serial number with an original tag on Blockchain. That's not exactly what NFT's can be. These are low shill efforts on ETH and some rich dudes/madams decided to inflate the price by buying things from their alt accounts to create demand and the rest of the morons followed.
Real NFTs will definitely have a better outlook if unique items are given out in rarity or truly earned by some through dedication: A platinum trophy as an example. However the true value of NFTs are that you will own those items and resell them at your own volition on interchangable blockchains. It will be a brand new virtual asset class of your own. However, the game brand must have value in the first place to be able to net high revenue. Think CS Go Knives but not dealing with Steam Marketplace only which can also be interchangeable in other games if Valves allows it and developers code it into their games.
Give it 2-3 years with the next crypto crash for most of these jpeg nonsense NFTs to die out. Real world usecase will probably be a thing by Metaverse. However, if the platform has no value, neither will the asset. So those AAA developers are well on their way in making tons of money. Even though I am against MTX and GAAS. NFT's are a bit more exciting that I can actually sell items I don't need.
Outside of that, other usecases of Blockchain is this and it will never happen. Lets say I buy AC Origins on Ubisoft, the Blockchain smart contract will validate that I have the 3rd party game. Now instead of Xbox, Sony, Steam having their own storefronts for mentioned 3rd party game, companies can sell their copies one time and validate all storefronts that I indeed have bought the game so it is available anywhere to play including my save data. But this will never happen seeing how greedy Publishers are with what happened to GeForce Now as an example.