Can't one use personal due diligence to weigh the risks of the "possible" charismatic schmoozer? The adventure seekers had plenty of time to decide whether to believe Rushton (or not).
Sure, although a huge percentage of people have personalities or conditions that make them more susceptible. Not a fan of individual humans deciding, for example, who is a good neurosurgeon. Not interested at all in whether other people find a particular person to be expert; I want experts and data. I think I may be unusual.
Among the many conditions who are susceptible to those who are charismatic grifters there are personality disorders, neurological issues (particularly autism), mood conditions (particularly depression).
That's why we have laws. We do not allow charismatic grifters to practice medicine without a license (if they are caught they are punished; if a person suspects someone is unlicensed, they have ample legal recourse). We do not allow people to pretend to be high school teachers just because they are charismatic (it's tried, a lot, and people even forge documents). Instead, we have approved systems of acquiring test scores, licensing information and educational documentation that is received in ways that make it hard to forge (this is true where I live - not at all true everywhere in the world).
Personal due diligence, unless it includes the ability to read expert literature, is not going to help a person decide whether a seagoing vessel is seaworthy. I wouldn't have the first clue about how to assess a possible cruise ship, or its captain and crew, much less a submarine. OceanGate apparently lied on its website (according to the letter posted here from the submersible/submarine licensing agency). It never sought licensing or approval, it never had licensing or approval.
This is similar to your doctor (who has privately studied medicine and knows quite a bit) having printed out their diplomas (forgeries) and put them up on the wall.
How would you know that until some kind of malpractice occurred? There's no easy way to check if those diplomas are real. We trust in others (some of us trust too much, some of us are fairly paranoid - WSers tend to be concerned and wanting more facts, but very few of us could tell whether a doctor is who they say they are - even getting records about disciplinary action from the state level is something that isn't immediately intuitive. Trusting on-line doctor ranking systems is even more futile (shady doctors write their own responses)
Would you be okay with having to do due diligence about every teacher, doctor, etc.? Product liability law fortunately
There are other elements as well. With airline pilots, there is random drug and alcohol testing. I like that. I like knowing my pilot is likely sober. With airline pilots, there's a co-pilot who is also tested. The two are supposed to observe and report each other. I like that too.
But when I get on the plane, I could still be harmed by the negligence or lack of sobriety of a particular pilot - and that's not something my personal due diligence could never uncover. If I died because of pilot error, no waiver of liability would stop my heirs from successfully suing and settling a case with the airline. But my personal due diligence would not be able to stop that.
We need regulatory commissions. We (the US) have them. CEO Rush evaded them.
Having licensing does not stop people like Rush from going offshore. We probably need better messaging around offshore enterprises. I bet these billionaires would not have put their fortunes into a bank in a not-quite-a-nation offshore entity (like Bank of Metohija - most would not put a large sum there).
But I bet not even one of the passengers realized this was a flagless vessel (the Titan - it flew under the banner of a flagged vessel, the Polar Prince) operating in and around international waters (so very difficult to regulate).
They knew it was dangerous, but they didn't know there was no regulation or licensing or inspection or, even, ownership of the Titan (it was built from stuff purchased separately; there was no registration of it or specific ownership of it, except that OceanGate claimed that it (a non-profit) owned it.
I bet the universities and others who donated to get their logo on the homepage at OceanGate are feeling pretty awkward today. What is missing, of course, is any evidence of national registration or, more important, licensing of the vehicle (there are 12 other deep sea-going tubes that are registered; Titan is the only one that wasn't).
IMO.