Now when you get a photo attachment in a Gmail message, you can save it directly to Google Photos with a new "Save to Photos" button. You’ll see it next to the existing “Add to Drive” button on the attachment and while previewing the image attachment. Currently, this is only available for JPEG images.
This new feature frees you from having to download photo attachments from Gmail messages in order to then manually back them up to Google Photos.
There is no admin control for this feature.This feature will be ON by default. For an eligible photo, you can choose the "Save to Photos" button which is alongside a similar option to "Add to Drive."
Rapid Release and Scheduled Release domains: Gradual rollout (up to 15 days for feature visibility) starting on May 26, 2021
Available to all Google Workspace customers, as well as G Suite Basic and Business customers. Also available to users with personal Google Accounts.
Google Workspace updates blog