"Nothing useful can be said about the security of a mechanism except in the context of a particular application and environment." --Robert H. Courtney, Jr. His First Law
Cryptographic mechanisms provide us with good examples. The Data Encryption Standard (DES) asserted that the cheapest attack was an exhaustive attack against the key. That remains as true today as it was fifty years ago. While the cost of such an attack may be trivial today, it might still be inefficient for low value short lived data. While generally disparaged and deprecated "Triple DES (3DES)" is sufficiently resistant to attack for most known applications and environments.
Similarly, while Google asserts that, using Schorr's algorithm and a quantum computer, one might be able to solve for an Rivest Shamir Adelman (RSA) or an Elliptic Curve Crypto (ECC) private key in hours to days, rather than decades, this would still be inefficient for many applications and environments. For example, while it might be efficient for decrypting a state secret with a life of three generations, it would not be efficient for surveillance of a large population. Think of how many RSA and ECC key pairs we create for protecting Internet traffic each day.
While we may need "post quantum crypto (PQC)" for some sensitive applications and hostile environments, RSA and ECC will be adequate for many of the applications that we use them for today for as far into the future as we can see.
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