Natural disasters are inevitable as we can't stop it from happening especially as developments advances and we continue to interrupt nature, natural disasters and bound to occur. And no doubt to, that physical means of securing our seeds phrase is the safest of all others ways of storing our keys.
Not all natural disasters can damage (destroy) your seed-phrases and pose a danger. There are regions where natural disasters dangerous for seed-phrases on physical media don't occur (like floods, earthquakes, volcanic eruptions, etc.). Therefore, if you choose the right location, then seed-phrase can be stored safely.
But there are risks created by man, such as armed conflicts, wars and other clashes that can happen almost anywhere.
Of course. There are areas where certain destructive natural disasters are not heard of having happened before. Such areas are safe for people there as they do live with no fears of any sudden disasters, hence, the safety of their seeds phrase especially for those with metal storage technique.
Nevertheless, arson do happen. And this isn't a natural cause but humans. Which therefore makes the idea of a different locations for our seeds phrase more meaningful and efficient than having it in a single place.
~snip~
To store the seed-phrase in 3 different locations, these "locations" (apartment, house or plot of land) must belong to you or your trusted persons. You don't plan to keep the seed-phrase buried in a public park, do you?
Also, these "locations" must be at your (or your trusted persons') disposal for a long time and without access by unwanted persons.
In general, in practice, implementing this point with 3 locations will not be so easy for most people. For example, your relatives, in whose house you stored the seed-phrase, can move to another place and other people will become the owners of this building, who will not allow you into this house (loss of access to the seed-phrase).
Before you will be deciding on the different locations to have your seeds phrase hidden, you should know that it's somewhere you can call your private property and not just any unsafe locations where any individual or family members can be having access at will. A bitcoiner should know this better than anyone.