tpm2-tss is not an implementation of a TPM, it's a client of the TPM protocol that talks to a server. The server in this protocol can be a real TPM reached by a linux device file or a TPM arbitrator (in kernel on in userspace) or a TPM emulator (the IBM one linked above), etc.
tpm2-tools are CLI utilities that use the tpm2-tss library.
tpm2-tools are CLI utilities that use the tpm2-tss library.