A TPM can harden a pin such that it is stronger than a biometric. As a simple example, suppose the TPM has an exponential back off algorithm such that you need

A TPM can harden a pin such that it is stronger than a biometric. As a simple example, suppose the TPM has an exponential back off algorithm such that you need to wait 1s after one wrong guess, 2s after two wrong guesses, 4s after 3, etc. No one is getting anywhere close to 64 guesses in that case much less the hundreds you might need for a 4 digit pin (assuming it isn't someone's birthday). However, you are correct that a fingerprint is faster than even a 4 digit pin. And even a TPM does not solve the problem of pin/password reuse and being easy to guess, it just makes it harder by giving you much fewer guesses.