The Android Open Source Project team is working on a function called “hibernation” which will reduce the amount of memory used by applications you are not using. This feature is still in early development stages but could be included in Android 12 (There is no official release date, but Android 11 developer beta came out in February 2020).
What is hibernation? If one user of a multi-user device decides to put the application to sleep, the application cache associated with that user will be cleared, freeing up some space… This option has already been implemented.
A more interesting situation arises when all users of a given Android device put the application into sleep mode, especially since only one user account is associated with most devices. Since this option has not yet been worked out, it is unclear what the OS will do in this case.
Judging by the name of the function that programmers are currently working on, such an application will not be permanently removed. Still, it probably will suggest a way to compress it to save space (along with the cache’s usual cleaning). Later, if any user wants to wake up the application from hibernation, it can be unpacked.
Note: this hibernation function seems, apart from the name, to have nothing to do with the hibernation function offered by some Xposed apps and modules, which, like the Doze algorithm built into Android, pauses the execution of apps on the idle device.