So then,

VeeSA says: "Hur durr, maybes needs encryptions?  Much dollars needed!"

And, yet, that is what the SHA hashcube DOES: Encryption.

The blockchain of some good and true coin (not debauched by diff forks) if it can deliver true security where Visa hath fumbled (all their 1000s customers robbed the last holiday) will see an adoption like none every before.  AND YET, that coin must think ahead as to how to provide TX identifiers that are true, but which do not contain payload that contains user data.

From a legal perspective, if you look at the crushing penalties for fumbling customer data, well, it makes one want to become a lawyer (haha not really) because of the sheer volume of litigation which is pending against companies that now owe the states millions of theorized-legal-dollars in future terms, because of recent data fumblings.

All acceptors of any customer identifiable data, shall suffer hard fines if they screw that fiduciary duty up.  That is what the code says.  So, the coin which brings POS security, will exploit the current milieu which is one of customer pain and theft-sufferings.