It’s a hush hush kind of thing. You advertise it’s to avoid discovery and you are openly admiting to liability should someone find out while trying to pull your execs email during discovery.
The excuse of resource contention provides plausible deniability
Yeah, this is really common. Normally there'll be one unrecorded/easily deleted means of communication, and people use that for discussing things that potentially could expose the company to legal liability.
But nobody ever talks about it (except on said un-recorded meetings. That reminds me, I should explain this to our junior today, so that he knows for the future).
The excuse of resource contention provides plausible deniability