Regulated and decentralized are not opposing ends on the same spectrum, under a mature government one can have both.

> Regulated and decentralized are not opposing ends on the same spectrum, under a mature government one can have both

The point is it's regulated irrespective of the government's maturity. If it only works under a mature government, it's superfluous as a social tool. (Technology usually is.)

it is, when the regulating authority is centralised

> [...] bitcoin“. As soon as it becomes popular, it gets regulated.

And, before it gets popular and regulated, it gets overrun by criminals?

Definitely the case with Bitcoin. I don't know about ProtonMail, though.

What is a criminal but a person who acts against pre-existing regulation anyway?

Bitcoin's 'criminal' use is/was 95% narcotics. In a world without a superficial 'war on drugs', where a state had no right to tell a citizen what to put into their own body, no user, no dealer would be criminal.

If you wish to fight crime, the solution might not be to 'make more things criminal', but to 'make less things criminal'.

On the other hand, I have been using bitcoin for cross-border value transfers where banks would have taken ridiculous fees, and I have used bitcoin for online micro-transactions where setting up other payment systems would have been expensive.

The fact that governments have regulated cryptocurrency does not change the value proposition of the technology.

The governments have also regulated cocaine. It didn’t work there, either.

Governments would certainly like to regulate Bitcoin, and many have passed laws to this effect. But it's still possible to use it in a way that effectively skirts all this regulation, because of its decentralized nature.