The pressure does not kill. Whales live down there. It’s the compressibility of water. At this depth it’s about 4% compressed. The cabin has 1 atmosphere of pressure, the water around it about 100. Through a microfracture water shoots in at the speed of sound in water (3x speed of sound in air) - that’s about 100 bars. That’s like a water jet cutter. It rips the microfracture open. Within a tenth of a second they get pressed to death by the compressibility of water.