There are some really cool things that can be done with NFTs (concert tickets, in game items that can be cross-game, etc). The most popular use right now is art. The really interesting thing is that NFT art is really close to real world art: both are ridiculously overpriced for something not very unique that is heavily driven by rich characters trying to hide their money. All art is dumb, not just NFTs. NFTs are just more liquid.