Android 12L: According to Google’s developer team Jing Ji, an Android 12 patch will allow you to disable the PhantomProcessKiller function, which aggressively limits the amount of subordinate operations an application can run. The new option will be available since launch on Android 12L, which is aimed at devices with larger screens.
Overall this is an efficient way to prevent apps from consuming a lot of CPU resources and therefore a lot of battery.
Problem for advanced users
It is common for power saving tools to disable or limit operations when they are put to work in the background. On some devices, Waze may lose GPS access when the app is minimized to answer a call via Bluetooth, for example. Thus, it is necessary to wait a few minutes for the program to receive information from the satellite again, causing the user to miss that last return on the road.
Most of these options can be turned off in the battery settings, even without Developer Access, but PhantomProcessKiller didn’t have this option even with Advanced Access.
For the standard user this shouldn’t be a problem, but for advanced users, heavier applications like the Termux Linux terminal emulator, PhantomProcessKiller would completely terminate the application without the user having any way around the situation.
Fix is coming
A patch that allows you to disable the tool in Developer Options has already been released in the Android Open Source Program (AOSP) and, according to a report on the Google Developers Forum, the fix is already integrated into the Android 12L code as one of the planned improvements for the special version of the system. In other words, it now remains to wait for the news to be widely distributed.