Apple has removed the ability to buy or rent movies and series when using the Apple TV app on Google TV or Android. With this you can only log in and look at what you have bought or borrowed on an Apple device.
Apple probably doesn’t want to give 30% to the respective platform operators, Google in this case. This is ironic because many software and content providers want to defend themselves against the 30% levy in Apple’s stores and Apple has always strongly defended this levy.
Or maybe users just don’t buy and rent movies and series in the Apple TV app if they don’t have at least one Apple device. Apple TV+ has a very limited range anyway and is usually only used by Apple customers anyway, so Apple may simply want to save the effort for the infrastructure of the app on Android.