This forum gets more and more detached from reality every day.
“NSA intends that all NSS will be quantum-resistant by 2035, in accordance with the goal espoused in NSM-10.”
Source: https://media.defense.gov/2022/Sep/07/2003071836/-1/-1/0/CSI...
Anything that is private today is private for a reason. That reason doesn't automatically disappear over time.
I don't think you've been paying attention to the news.
Also the US government isn't a great example. JFK was assassinated in 1963 and all records surrounding that still haven't been released.
The idea that people don't care about secrets across the span of decades is utterly wrong.
And the US intelligence community is the greatest data hoarder on the planet, rivaled only perhaps by the combined forces of facebook/google.
But I expect that in 5-10 years, most security systems designed by competent professionals (up-to-date OS security services, TLS servers, SSH servers, VPN, firmware update systems etc) will have post-quantum crypto enabled by default. And I expect it will take longer than that to build a QC that can break classical crypto.
More likely it will play out like the SHA-1 break: all professional security engineers should have switched off SHA-1 (at least for unkeyed hashing) years before any collision was found, and users who apply security patches should therefore by mostly up to date, but I'm sure some are still using the older crypto.
At the same time, from history it seems almost certain that, if indeed a CRQC ever gets built, a significant number of users will not have secure PQC rolled out on day 0.