Are people just expecting there's going to be enough digital fools to make a market?
A movie can be duplicated indefinitely. There's no guarantee your song will be appreciated as art. I'm not sure why you say you can't print out an image and hang it in your living room; we do that all the time at home.
I've personally never dabbled in NFTs, but I don't think it's fair to ascribe the inherent conflict between information and scarcity uniquely to them.