For people holding crypto assets which they don't plan to sell, it's a valid way to borrow other assets for use. Potentially for other investments. Definitely not just for criminals.

And overall, it's a demonstration of a financial product which can only be built in the space of decentralized finance. I do not know of another tool which allows anyone around the world to borrow significant amounts of money anonymously and without an account. Whether it's a net good for the world I don't know, but I do believe it's a powerful technology and space.