It doesn't look like any e-gold users were prosecuted, or like the grounds for prosecuting the operators of e-gold would generalize.
The government's response to a currency or payment system that could be shut down by shutting down a single "point of failure" is not particularly informative for predicting its response to a payment system that does not have a single point of failure.
The government correctly perceives allowing the man in the street to transact business or earn money outside of the awareness and control of the regulated banking system to be a threat to its revenue stream and to be an enabler of crime and terrorism.
That the government is likely to spin or outright create laws to protect its interests is a different thing to "this activity is possibly illegal".
I was given related advice while a cofounder of a startup venture. Forget whether you are legally in the right. If a powerful competitor is threatened they can sue on a vaguely credible premise they can destroy either your company or years of your life regardless of whether their superior lawyers foist it past the judge.
The letter of the law just doesn't matter all that much if there is a power imbalance.
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