Its possible not to be candid without even using lies of omission (and be on the losing side of a vicious factional battle) and get a nice note thanking you for all that you've done and allowing you to step down and spend more time with your family at the end of the year too. Or to carry on as before but with onerous reporting requirements. The board dumped him with unusual haste and an almost unprecedented attack on his integrity instead. A lot of people are reading the room rather than hyperliterally focusing on the exact words used.

If I take the time to accuse my boss of failing to be candid instead of thanking him in my resignation letter or exit interview, I'm not saying I think he could have communicated better, I'm saying he's a damned liar, and my letter isn't sent for the public to speculate on.

Whether the board were justified in concluding Sam was untrustworthy is another question, but they've been willing to burn quite a lot of reputation on signalling that.