Probably because many people associate NFTs with images. I've rarely seen NFTs containing chunks of text or audio files. Probably because many people prefer to see what they buy rather than read or listen to it. I remember there was even a little hype around NFT with famous tweets, but that hype quickly subsided and didn't get the proper exposure. Even the NFT, containing the very first tweet in history, has fallen in price many times over, as few people are interested.
Making NFTs out of tweets is ridiculous. After all, those same tweets are stored on centralized servers managed by Twitter. If the company goes down, so will the data stored on those servers. The Blockchain will only prove you had ownership of the NFT, but without the data/content, what's the use?
NFT creators aren't even thinking of storing the content on decentralized cloud storage networks such as Arweave or IPFS. They're only thinking about making money in the fastest way possible. If this keeps up, don't expect NFTs to be taken seriously anytime soon. Who knows what the future holds for the industry? Just my opinion
