Google started updating its account switcher last September. This account switcher is placed in the top right corner of all its Android apps. While, with this updation, this now getting more Material You and Dynamic Color.
Notably, this updation in the Google Account Switcher has first debuted and appears in Messages with rounded corners. While the button for “Manage your Google Account” is switching to a rounded rectangle from an earlier pill shape design. Although, it has not yet rolled out widely to other apps. On the other hand, the same has been live on Google TV recently, which just got its Dynamic Color redesign.
Additionally, Messages‘ latest beta version (messages.android_20221208_01_RC00.phone.openbeta_dynamic) is now becoming the first to get a Google Account switcher with Dynamic Color theming. This has been applied in two parts. Notably, the active account is now placed in its own Material You container. In place of using a line separator. While its background is darker than the rest of the account switcher to visually draw your eye to it.
Given the (mostly) uniform nature of the Account switcher, this new Material You design with Dynamic Color should roll out to all first-party apps. Google is likely waiting to finalize the design before doing so. This redesign is a step in that direction.