One successful quantum computer and all digital "security" as we know it ceases to exist.

Indeed it does, the issue is that successful quantum computer [for solving existing digital "security"] is always 10 years away, because guess what, size of keys for encryption is not staying in place, and growing qubit count of quantum computer is a task significantly trickier than slapping larger register on a CPU (which is not trivial task either).

Governments and banks can roll out new currency to replace the old if it becomes a risk for them

That's identical to saying existing currency will become scrap paper, not any different from crypto.

One successful quantum computer and all digital "security" as we know it ceases to exist.

Indeed it does, the issue is that successful quantum computer [for solving existing digital "security"] is always 10 years away.

Governments and banks can roll out new currency to replace the old if it becomes a risk for them

That's identical to saying existing currency will become scrap paper, not any different from crypto. Wouldn't be first time for my family tbh.

For the record, i am not the guy to own any crypto because i am too broke for that.

One successful quantum computer and all digital "security" as we know it ceases to exist.

Indeed it does, the issue is that successful quantum computer [for solving existing digital "security"] is always 10 years away.

Governments and banks can roll out new currency to replace the old if it becomes a risk for them

That's identical to saying existing currency will become scrap paper, not any different from crypto.

One successful quantum computer and all digital "security" as we know it ceases to exist.

Indeed it does, the issue is that successful quantum computer is always 10 years away.

One successful quantum computer and all digital "security" as we know it ceases to exist.

Given that there's not even a theoretical certainty for breaking sha256 with quantum computing any more efficiently than classic approach (and breaking existing algorithms like shor's algorithm vs RSA collides against scaling problem of current quantum computers)... i am on the side of suspecting that anyone telling you "10 years away" wants to con you.