I do not know specifically which issue/law Google is looking to marshal SMB support around with this
But it is part and parcel of their long term efforts at astroturfing state and federal elected officials whenever there is even a whiff of regulation in the air.
See
Google Automates SMB Emails to Congress to Plead Antitrust Case and these appeals go out anytime antitrust, privacy or moderation issues rise to visibility.
And their argument is always the same... "your small business will lose access to free tools" or "your small business will suffer if WE get regulated" and whenever I have looked it has been a totally self serving bunch of horse pucky