Google started rolling out an updated user interface for Gmail in February that pulls Meet, Chat, and Spaces closer and applies more of its Material You styling effects. Starting today, it’s becoming opt-out instead of opt-in, so your account will switch over to the new view by default pretty soon.
It’s not a huge change, but as Google transitions through its current flavor-of-the-week messaging app and weaves its Workspace suite into a better competitor for Office, this puts more of a focus on the updated experiences.
If you can’t tell what’s different here, the updated UI collects buttons for Mail, Meet, Spaces, and Chat into one list at the top of the left rail instead of showing several conversations from each one in a list. They’re still easily accessible without having everything on screen at once, and you can quickly jump into a conversation in any one section as a list will pop out when you mouse over its icon.
And if you just want to have one particular form of communication on screen without the others (like Gmail), it’s a little easier to do that since Chat and the rest aren’t listed underneath your inboxes and labels anymore.
According to Google, you can choose which apps are included there in the Quick Settings menu, where you’ll be able to switch back to the old look if you prefer. Unlike the usual 15-day rollout for new features, Google says this one is an “extended rollout,” so while it’s coming to Workspace and personal Gmail accounts alike, it could take longer than a couple of weeks for your interface to change over on its own. If you just want to try it, you should be able to opt-in (and back out) from the quick settings menu right now, as long as you’ve already switched to Chat from Hangouts and positioned Chat in the left-hand menu.
Source: https://www.theverge.com/2022/6/28/23187304/google-gmail-ui-opt-out-rollout-chat-spaces-meet