> The argument that "security is pointless unless it can prevent <nation-state> from obtaining the data" is a really tiresome strawman.

This sentence is a strawman as you've invented the opponent's argument (literally no one has mentioned the NSA), just for what it's worth.

Your assertions that:

a) An attacker would have to rely on keylogging

b) Keylogging is a substantial barrier for attacker

are unfounded.