Because it is. Total surveillance only works if the people are forced to wear the tracking collar. The next steps are tying it to CBDC, that require a phone number to access your wallet, and tying it to realid/passport to restrict travel.

2FA has become the wedge to break privacy into a million shards.

There are services online dedicated to temporary account activation phone numbers to bypass Google's requirements, but most of them can only receive messages. Requiring the user to send an SMS seems like an excellent method to get rid of those services so that bots can no longer use them.

I don't really see the point of a privacy-preserving workflow when it comes to a Google account. It's not like they need to know your phone number to track you.