If you're asking about TPM in general, the answer is, among other things, cryptographic identity tied to a device. So, assuming it's everywhere, no more phishing for user credentials, no more password re-use attacks, no session exfiltration, and those are just a few - there are many more. Personally, I would rank those threats as being the top threats for the vast majority of users and organizations, so that's not nothing.

If you're asking about 1.2 vs 2.0, 2.0 makes considerable progress on the original specification both in terms of hardening of the TPM and its capabilities, allowing for it to be used in a much more broad set of authorization and authentication schemes.

If tomorrow every user had a TPM, and major services supported it, it would massively change the security landscape - I really can't stress enough that it eliminates some of the most widely exploited attacker techniques.