A thriving market for magic beans doesn't make the magic beanstalk real. Cryptocurrencies are often involved in modern versions of pump and dump scams, ponzi schemes, investment fraud, unregulated gambling, and large-scale money laundering.
Many applications of cryptocurrencies are questionable. Their real effects are proliferation of ransomware and other criminal activity, and PoW-based schemes contribute to e-waste and climate-affecting energy waste.