It'll be a sad type of fun watching him become another disgusting and disconnected bazillionaire. Remember when Mark was a Honda Fit driving Palo Alto based founder focused on 'connecting people' and building a not yet profitable 'social network' to change the world?
This is a repeat of the fight for talent that always happens with these things. It's all mercenary - it's all just business. Otherwise they'd remain an NGO.
I can't help but think that it would have been a much better move for him to get fired from OpenAI. Allow that to do it's own thing and start other ventures with a clean reputation, and millions instead of billions in the bank.