- to exchange crypto you need an internet-connected computer, you can't exchange anything from a human to another human being, many might state that's not different than bank transfer on X.25 but it's different from cash, and that's just the appetizer that simply mean: to participate to the economy you need to be connected, and you can choose between few big ISPs for that and you need a computer chosen between the very few manufacturers we have around the world, typically a computer filled of proprietary FWs like moderns ones;
- cryptos are based on a "blockchain" concept, witch means on a giant append-only file, that's means sooner or later home computer will have not enough storage nor bogomips nor bandwidth to operate cryptos "freely", exchanges will be mandatory by technical needs, not by laws, since only big server farms will be able to process transactions at a viable speed. At this point the "free" and "open" part is gone. At this time cryptos are like today's banks, BUT without State laws and protection, an exchange can be in an exotic place, can disappear and start over with another name etc it's costumers are and will be totally powerless;
- not only: since we pay "on-the-go" naturally with cryptos wildly adopted that means de facto mandatory smartphone always with any humans, like the wallet in your pocket, and smartphones not only means already mandatory exchange on a hyper-surveilled platform but also means depend on them for anything, being unable to even buy food without and integrate social scoring it's natural.
Take the above and observe what WEF want in terms of digital identities and payments systems https://www.weforum.org/agenda/2021/01/davos-agenda-digital-... perhaps together with https://www.protocol.com/entertainment/upland-augmented-real... and you close the circle: cryptos so far are not there, but have created a narrative that digital currencies are good and needed. Most people do no even know the difference between cryptos and CBDC, in the end for most means just numbers inside a mobile (cr)app or website. I expect in a decade a final success of the cash-less push, with the sole payment system remained a smart-phone based one, connected and surveilled, of course linked to a digital ID, of course linked to social score: wellcome to the "western version" of modern China, evolved to surveil even more.
Oh beware a thing: if you want to wait and see because seems too extreme to be true... Once inside such systems, once our IDs, payment systems, social scores are implemented only an improbable civil war can overthrown them, and in a hyper-surveilled and hyper-centralized society where from ovens to toothbrushes to cars anything is connected a civil war means a thing: any Citizen can only let itself die hoping that's enough to crash dictatorship dominance, because it's impossible to fight if you can't eat, you can't travel because all the means to do so are connected and centralized in few hands. Take then a look as software these days: we tell for decades that we need FLOSS etc, what happen in the meantime? Emails are still there, only for 99% are webmails, so nothing practically different than a proprietary service like WA or Telegram. Dependence on few giants is far bigger then ever, anything desktop-centric and P2P-centric is disappeared, even tech communities are now on Reddit, HN etc, witch means on proprietary third parties platforms instead on open Usenet no one really own. Most people, devs included, live on APIs and cloud. Did you really think we are so far from the society depicted above? In the IT we already almost owning nothing "and being happy", actually IT is the core of our society functioning. Companies, especially from the finance sector have internal social score since decades, people think a society like a company, witch means a hierarchy not a Democracy etc...