Claustrophobia shouldn’t enter into this. Very few people “like” being in confined spaces, let alone being trapped in them. But it’s safe to assume that far fewer people would enjoy being crushed to death by rubble.
And while I agree that if you’re paranoid and wealthy enough to buy one of these, you should probably live in a building with modern structural reinforcements designed to help prevent an earthquake-caused collapse. But as we’ve seen with the Millennium Tower, spending a pile of money on fancy new construction doesn’t mean you know for certain that your building is actually safe.
So yeah, if you have both the cash and the paranoia, why not buy an earthquake shelter bed?