That's not why we should deny cryptocurrency. We should deny it because it is fundamentally bad, it serves no purpose besides scamming and fraud. The technology is broken and can't ever achieve its stated goals except by pure luck, at which point it is no better than any other solutions.
>they cannot read my data, access my devices, or take the money
Yes, they can. A dedicated aggressor (i.e. a nation state actor) will just torture and blackmail you until you give that up. Of course it gets harder for them if they kill you, then they would have to brute force your data. But then why would they need access to your devices, if you were the target they were trying to get rid of? If your private correspondence was with another party, they can also just blackmail the other party into giving up dirt on you. Cryptography can't actually do anything about these classic "meatspace" techniques.