I was half tempted to reference that myself, but if I had, someone else would have replied with all the testing SpaceX does.

(The recent explosion was such a test).

(And that sub had apparently been to depth before? I didn't follow the details…)

The fact that one billionaire's company does a decent job testing doesn't mean that billionaire customers are paying attention, or that other billionaires aren't happy to be beta-testers for a different company that doesn't believe in testing or safety or regulation.

I think the OceanGate disaster just shows that billionaires aren't any smarter or more rational than the rest of us.