You have a point. In some ways, NFTs can be thought of as penny stocks that are looking for a pump before the dump. But as others are saying, high value collectibles would be a gray area, and I think we all agree that the art world with regards to paintings and other artifacts can be just as speculative.
But just as a penny stock or Enron stock might not be representative of the entire market, NFTs are not representative of the crypto market.
The thing with penny stocks though is that the pump is usually because of some promised future performance that never materializes. With NFTs, there is no future cash flow or promised productivity. Its only promised future higher value. And this is exactly what art is based on. The Picasso painting will never produce anything or pay a dividend, but you wouldn't think of it as a penny stock. So I think most people going into NFTs realize they are only buying it hoping for price appreciation. And in fact, some NFTs might in the future even give you special perks for being an owner. I'm not saying I agree with it all, but for those who see the value, why stop them?