The short version: You have less than a month, and no, it's not optional. Via Forbes:
Hot on the heels of a warning about a dramatic rise in the number of attacks targeting Gmail users, comes a timely reminder that Google is about to force Google Workspace users into taking security more seriously. Starting September 30, access to your Gmail account from “less secure apps, third-party apps, or devices that only require a username and password to sign in” will no longer be supported. This latest move is part of an effort to stamp out what Google refers to as an “antiquated sign-in method,” one that puts Gmail users at greater risk of compromise from those who seek unauthorized access to your Google account as it involves sharing your credentials with third-party apps and devices. This forthcoming change impacts all Google Workspace customers, Google said.
Google made it clear that support for what it calls less secure apps, along with Google Sync, would be dropped in a Google Workspace update posted almost exactly a year ago. The decision to tighten up authentication security in this way was first suggested in December 2019 but, with the impact of Covid taken into account, was suspended in March the following year. Now the deadline for getting your Gmail, plus Calendar and Contact accounts, in order is fast approaching.
