That isn't taking into account how frequent relative to all such target objects an attack occurs. If a (much?) smaller percentage of houses get burglarized vs.

That isn't taking into account how frequent relative to all such target objects an attack occurs. If a (much?) smaller percentage of houses get burglarized vs. number of phones broken into, then security requirements are not really comparable. (Note that I have zero idea of or even guess for the sizes of either, though.)