I see two of nineteen investors were also invested in FTX (Insight and Ontario teachers). With hindsight that's a bad investment although they probably recovered their money here so probably not their worst. Does this actually tell you they are stupid or insane?

I think that's one possible interpretation but another is that these funds choose to allocate a controlled portion of their capital toward high risk investments with the expectation that many will fail but some will pay off. It's far from clear that they are crazy or stupid.

They recovered their money but what about the opportunity cost? Its actually an economic loss. In retrospect given the risk it was a pretty terrible investment.