It does. But cache clearing only goes to a certain point after that it will stop you from updating apps and installing new apps, until you free up space by uninstalling an app.
User never has to manage cache space which has always been the case. Also your normal user cannot do that, without system level privileges. Third party apps where to able to call adb directly on FireTV which is not the case on other Android devices with GMS. In fact if you build Android with access for third party to call adb, Google will never let you pass CTS and you cannot have Google Play on it. It’s a huge misstep from security point for Amazon sell devices with adb access for third party apps.
Giving the user a prompt is a bandaid on the OS failing to do its job.