You're mixing up TPM 2.0 (which can also go on the SPI/LPC header that a TPM went on) with AMD's fTPM and Intel's PTT.
AMD fTPM and Intel PTT are implementations of TPM 1.0 and 2.0 on a microcontroller inside the main CPU; you can (and people do) have an external TPM 2.0 chip on the appropriate bus instead of inside the main CPU. And you could do remote attestation with TPM 1.0, not just with TPM 2.0.
TPM 2.0 is not always "right in the processor"
AMD fTPM and Intel PTT are implementations of TPM 1.0 and 2.0 on a microcontroller inside the main CPU; you can (and people do) have an external TPM 2.0 chip on the appropriate bus instead of inside the main CPU. And you could do remote attestation with TPM 1.0, not just with TPM 2.0.