Google Assistant’s Light Mode has been disabled. For example, if you want to run Google Assistant in light mode, then you cannot do this now. Now, this is possible only if your phone runs on the Android 12 version instead of the Android 13 version because Google Assistant in Android 13 will have only a dark mode.
But it seems that the users did not like this decision of Google because the users do not want it.
Google’s plan is that all its apps should be similar and work equally on as many platforms as possible. For example, on smartwatches, Google Assistant is only offered in dark mode as it saves power.
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Google mentions it in the issue tracker
“In order to provide a more helpful visual experience across all of your devices, including Pixel Watch and Google TV, when interacting with the Assistant on mobile devices, light mode is no longer available. Assistant now appears dark even if you have turned off the dark theme in phone settings.”
According to a Googler on the Issue Tracker, this is an intentional design decision.
Google Assistant will always appear dark on mobile when you’re running Android 13, even if dark theme is disabled in settings. https://t.co/qGNK5cWZur
— Mishaal Rahman (@MishaalRahman) October 31, 2022
To offer a more helpful visual experience across all your devices, including Pixel Watch and Google TV, when you engage with Assistant on mobile Light mode is no longer available – it will now have a dark appearance, even if you have Dark theme turned off in your phone settings.”
— Mishaal Rahman (@MishaalRahman) October 31, 2022