I think the TOR browser does a lot more than just run a browser through TOR. It uses Firefox's built-in fingerprint counter-measures; it spoofs the user agent;

I think the TOR browser does a lot more than just run a browser through TOR. It uses Firefox's built-in fingerprint counter-measures; it spoofs the user agent; it starts using specific window dimensions to counter resolution fingerprinting; and many more things that I am probably not aware of. Running a random browser through the TOR network does not really anonymize you from the myriad number of ways a website can fingerprint you, and the TOR browser / Firefox go to some lengths to protect you from those things too. I think Google, being an advertising company, would have a conflict of interest in providing that same level of anonymity.