It's hard to imagine a plausible path to payment digitization without states asserting a) currency controls and b) some degree of visibility on transactions. I think on the latter they'll take a "well if anyone can see it, we should be able to " and "KYC is needed" etc. stance. The only way to avoid anyone seeing it will defeat (a) an not be acceptable to them. This would relegate to same status as any other black market, with better/broader tech.