A very powerful story that explains how the dreams of some can turn into a nightmare (for many).
When desires to push boundaries involve 'life & death' risks, it's sobering how many people perish before someone learns how to do it correctly and safely. Example: In the race to advance aircraft design in the early days of aviation, it often took a dead test pilot to learn what was wrong with the design. Thankfully with modern computer aided design and simulations, potentially dangerous characteristics of a new experimental concept can be known even before construction of a prototype begins.
It seems that many knew this OceanGate submersible was operating at the very limit of its design capability. Exceeding that limit seemed almost inevitable according to Cameron. And you can tell that he's still angry about the results of OceanGate's 'miscalculations'.