> Which means air space that can get crushed

Would note that air isn't the only substance in a phone that compresses under 38 MPa. (Batteries come to mind.)

Air is the only substance that compresses to any significant amount. When you apply pressure to a battery from one side it may deform, but I would expect that the battery wouldn't be crushed because the pressure is from all sides - unless of course there is air in the battery - I'm not a battery chemist so take everything I say with some salt.

Note that I would expect water to seep into a battery at this pressure and that will cause all kinds of issues - including chemical fires underwater. Just not crushed batteries.