Well, for starters, Musk? As an investor (rather, lead capital provider) in a non-profit, he was blindsided by the decision entirely.
And before anyone criticizes me for defending his viewpoint, let's assume this: if Musk's $100 million investment were to be replaced by 100k HN users investing $1k each into a non-profit focused on safe and "open AI", do you think they would be uniformly happy about this decision?
You can perfectly have an AI that is powerful if you have the investment backing (like Musk provided). You can develop stuff out in the open like most software non profits do (case in point, the Linux Foundation), instead of playing Microsoft's slave.
An open AI is safe inherently, since it means that it can be easily ripped apart and thoroughly studied for exploitable points, unlike some closed black box system. Having Open AI be some closed system does nothing to reduce the number of bad actors - they will all choose to exploit Open AI's system once given the opportunity.