At the end of August, Google deployed the new Google Play Store interface, a full-fledged facelift that replaced the aesthetics we were used to by Google Material theming. It is a cleaner design line, with a more premium appearance and, as you have observed, very white. That not only seeks to make Google Play a more attractive store, but prepares it for the dark theme.
As it happened with Gmail and Google Drive, the dark theme of Google Play Store is already starting to poke. In XDA they have received it in a Google Pixel 2 XL with Android 10 installed and, apparently, there seems to be a toggle that allows you to switch between one mode or another, as on Twitter.
Dark theme for the Google Play Store
As collected in the developer forum, the dark theme of Google Play applies to the entire interface. From the main screen to the application tabs. The background turns dark gray, not completely black. Something that will be noticed much more on AMOLED screens, which will not turn off the pixels completely.
As you can see, the text becomes white to contrast with the background. And the green details of the Android application still existing. We see them, for example, in the installation buttons, the name of the developer. Alongside with the categories and the stars of the reviews.
The colleagues from XDA confirms that they have activated the dark mode in the phone settings, but that at no time they have forced the appearance of the dark mode in the Google Play Store. This dark mode does not seem to be able to be forced at the code level. So it could be a server-level update, and not available to all users.
Google recently confirmed that it had plans to bring the dark mode to most of its applications with the launch of Android 10 and, theoretically, this should be activated by activating the dark mode from the phone settings as in iOS 13.