Moxie Marlinspike explained the reasoning behind this troll project in a Twitter thread dated October 13. He wants people to be able to see what you’re buying when you buy an NFT. His NFT joke is a reminder to be cautious. After all, the token’s digital metadata is stored on the blockchain, but the digital image itself is not. The files are stored off-chain by image hosting sites. According to Moxie, this means that anyone who controls the URL host can modify the NFT image at will.
Which means also if that site goes offline (which it will at some point in time) the NFT is effectively rendered useless and non-existent... The owner of the NFT merely owns a verified link to something someone else is hosting.
See Moxie Marlinspike's NFT Joke highlights a major Problem of NFTs
Moxie Marlinspike is the founder of Signal, a secure messaging service and has now released an NFT. It shows what's wrong with NFTs.