I know the title says "in your TPM chip" but the method described does not store your private key in the TPM, it stores it in a PKCS keystore which is encrypted by a key in your TPM. In actual use the plaintext of your private ssh key still shows up in your ssh client for validation to the remote host.
The recommended usage of a yubikey for ssh does something similar as otherwise your key consumes one of the limited number of slots on the key.
The recommended usage of a yubikey for ssh does something similar as otherwise your key consumes one of the limited number of slots on the key.