Not so sure about that. It reads to me like there is a personal scandal on the horizon that has come to the board's attention, and the board feels their hands are tied. Hard for me to believe its business decision related; Sam is elite in this regard, and is not really incentivized to violate their charter.
Bummer in any situation... the progress in this domain is truly exciting, and OpenAI was executing so well. This will slow things down considerably.