No. PFS is about when messages are in transit. Sure thing, it makes sense to encrypt them with ephemeral keys rather than a long-living ones.
However, that particular point I've quoted was - as I understood it - about message archives. Short-lived keys are just fundamentally incompatible with long-term storage. We either keep data, or we don't.
PFS helps for about another point raised, "if a key is broken or leaked..." (but has a trade-off, as it requires some sort of key exchange)
> However, that particular point I've quoted was - as I understood it - about message archives.
In a sense you're right, but the archive in question is the one your adversary accrued while they were intercepting your in-flight emails, which you encrypted with your static key. Any archive you have control over is sort of beside the point.
However, that particular point I've quoted was - as I understood it - about message archives. Short-lived keys are just fundamentally incompatible with long-term storage. We either keep data, or we don't.
PFS helps for about another point raised, "if a key is broken or leaked..." (but has a trade-off, as it requires some sort of key exchange)