This whole assumption that TPM is a secure way to store things is ridiculously faulty. It's an interceptable i2c bus, and there's multiple tools available since 0.9 that can recover keys from both cold RAM boot and from interception of the i2c bus.

If your laptop gets stolen, the thief also has your keys and can also decrypt the hard drive, which the TPM storage initially was supposed to have been invented for to actively prevent.