Fungible tokens (FT) and Non Fungible Tokens (NFT) is't new idea but recently it has come to light with few new projects. Fungible is changeable or replaceable or interchangeable. Non Fungible is just opposite of Fungible. It is not interchangeable or replaceable. I still don't rely on this trend and i consider it's a new hype.
I think you are absolutely right because use case of NFT is not very strong, it is digital art and attracts who love art but paying huge cost of NFT is not possible for general investors/traders in crypto space, only high worth client can afford this kind of art work. I am afraid this tre4nd will not long and die down soon because mass adaption will be difficult due to weal use case..