> That's the stuff those explorers (and the people backing them) were made of.
They died all the time. https://en.wikipedia.org/wiki/List_of_lost_expeditions
I don't know why that's laudable: if you die before you make it back, for most of these locations, that means whatever you've learned is lost as well, and someone has to take identical risk to learn it for humanity again.
Seems to be better to see the cracked pane, return to the surface with your lives, write a letter to your submarine enthusiast magazine group or whatever the equivalent of a web forum was back then noting that such and such glass installed in such and such way cracked at N depth, try a new method, and dive again.
> No wonder nobody has been to the Moon in 50 years.
Why bother when the ocean is infinitely more interesting?