Since GPG and openssh support the TPM for some operations, I am tempted to store secrets in the TPM instead; I think a hardware safe is better than messing with persistent envars and having to pay attention to children etc.

But I am very nervous about doing so, since I have heard bad things about the reliability of the TPM (limited writes or something?) and locking myself out of important places. Any people with experience using the TPM for secrets in Linux?