Yes, TPM without a password is a step up from no encryption but TPM with even a weak password is a huge benefit.
Of course I am assuming that the TPM works correctly. Vulnerabilities in that may be more likely than with software crypto. But that is a difficult tradeoff to evaluate.
Use the TPM as an additional layer of protection. In combination with other things as well, heck even the encryption built into an SSD. So if any one fails, it's still better than nothing. All with separate, uncorrelated passphrases.
Of course I am assuming that the TPM works correctly. Vulnerabilities in that may be more likely than with software crypto. But that is a difficult tradeoff to evaluate.