Question about NFTs

The common response I see to people saying just right click and save is “ok now go sell it”. What stops someone from going on the same platform and minting it again?

For example what stops me from downloading the image from open sea and then minting it as if I made it? Are copy-write laws actually up to date enough to cover NFTs from a legal perspective? Do the images store some sort of data that the blockchain can detect duplications?

Thanks!