If you don't want to "be an asshole", set a clear company policy and move on.
Having been in the position of needing to access historical e-mail records while investigating CFO malfeasance and fraud, I'd say its downright irresponsible to not have the ability and policy necessary to monitor and review communications in extenuating circumstances.
They're not being "disingenuous". Ironically, speaking of trust/management, criticizing people's personal motivations like that is precisely one thing I'm taught not to do, for effective, healthy teamwork. (Whereas, if I must investigate antagonistically, like if a boss is harassing employees, I must assume the possibility.)
As for criticizing motivations, disingenuity was the more polite assumption compared to the alternative: that he is ignorant of the legal, technical, and historical context to the degree that he actually believes HipChat's changes are unique or novel or questionable in any way.
Entities in a technologically privileged position are limited only by policy. The fact that he accepts that truth simply by relying on SaaS demonstrates the significant incongruity of logic at question here.
The entire point of my protest to this change is specifically to stop either myself, or any member of management team from having a "technologically privilege position".
Your arguments about SaaS are irrelevant and juvenile. Just cause Atlasssian, or any SaaS provider, has access doesn't mean I, or my management team, should.
Saying "well we run our email server in house so we just solve this problem with a policy" is fine.
Hardly seems irrelevant to me, and the free pass you give to SaaS is nonsensical and hypocritical.
Second, simply because something is "status quo" does not mean it's OK.
As this is my company, I can chose to run it in a way that doesn't make me feel like an asshole.