PP, I believe the TPM provides the ability to hold data (e.g. authentication of a device or a root of trust) in a non-accessible space on the electronic device (e.g. a PC). The ability to wipe a hard-drive clean or to jam a cell phone doesn't really require a TPM, software is used for that. What's unique about the TPM is the degree of certainty which one has in device authentication prior to using such an application. Apple doesn't need a TPM to perform that, the software will perform it. Just not as secure, which, of course, could turn out to be a problem.
JMHO,
Svenm