I wonder a lot about the motives of the original sender sending that message.

Is it simply a way to spread FUD and discredit openbsd?
Is it a personal gripe with the accused?
Is it an attempt to manipulate what is used in the market?
Is it outright lies
Is it outright truth and genuine altruism?

While I suspect we'll never know completely for sure, it makes an
interesting point. Is it genuine? partially genuine? how much truth is
in there? if it's true how much of this mattered and has it since been
fixed? (as that code when through a lot of fixes since that time)

Of course in these days of binary only blob drivers, I don't think the
government need resort to this sort of tactic these days. Those nice
binary-only drivers everyone loves running for video and wireless will
ensure that there are nice places in your favorite Open Source project
that can be coopted quietly by government organizations and have
access to your entire kernel. No need to be subtle.