Yes, on the one hand, they enable a lot of shady illegal business, but in the other hand, they also destroy the environment while doing it, so it's really a toss up whether cryptocurrency is good or bad overall!
bitcoin is forecast to uses about 150 TWh of electricity this year vs all other datacenter operations foretasted to use 1000 TWh. Bitcoin is esitimated to be about 52.4% sustainable energy (renewables plus nuclear) where datacenters are 42% sustainable energy.
Equating the concept of cryptographic currency with specific implementations such as proof-of-work just shows that you have no idea what you are talking about.
The importance of financial sovereignty can not be understated, whether you understand that or not.