Given that the Columbia disaster occurred in the middle of those 32 years, I'm not sure that follows....

Somewhat true, I'd say that risk-averse is more appropriate than safety-obsessed. For such organizations, being "safety-obsessed" usually means a massive amount of bureaucracy around certain known risks, but such organizations don't tend to be consistently good at finding and addressing unknown risks.

You can be safety-obsessed and still have accidents when you're doing something as risky as space travel I think.