If people are willing to give a lot of money to a cause, sometimes that means their concern about that cause is real.

None of the info you provided really falsifies the Occam's Razor hypothesis: Anthropic is a public benefit corporation with a public benefit mission to "responsibly develop and maintain advanced AI for the long-term benefit of humanity". You don't have to like or trust them, but they very well might be sincere. For example here's a talk that was given 10 years before Anthropic's founding: https://vimeo.com/158576192