This is wrong. A digital image can create real value. Just because you don't value it, that doesn't mean someone else doesn't. Just because you can create a copy of the picture, you still do not own the NFT. You can't copy the NFT, no matter what you do. It would be like saying that you can copy dogecoin by making another chain with the same name and picture and then give yourself coins. You have coins called dogecoin in that case, but they are not the real thing. 
Not if it's an image obtained from the Web. I mean, "copy and paste" JPEGs which are submitted by anyone as a "unique NFT" on the Blockchain. Real value comes from creative digital art or unique masterpieces not found anywhere else. NFTs with limited releases (supply) meeting such criteria, would surely become valuable in the long term.
Despite NFTs' potential to transform the collectibles industry, the hype is quickly fading away as people move on to the next big thing. These days it's all about "meme" coins, AI-based tokens, and "shitcoins" (like XRP). The market is so speculative these days, that any "garbage" can quickly gain traction and make a few early holders rich in the process. Utility-driven projects often see a chance for success (except Bitcoin). I hope things change in the future and trends like NFTs and ICOs make a comeback. Crypto land is full of surprises, so expect the unexpected.