"Risk aversion" here is more a synonym for "prefer planning ahead and trying to account for everything in advance instead of using an iterative trial and error approach". SpaceX is very trial and error focused, which means they learn more quickly. It doesn't mean that their end product, e.g. their Dragon capsule, ends up being more (or less) risky to use for humans than, e.g., NASAs Orion capsule.
