So, the media DRM toggle switches from the hardcoded hardware ID to a software DRM. Creating a new DRM key.

https://developer.android.com/reference/android/media/MediaDrm

Geto uses shizuku (an app that allows for adb/shell functionality) to change settings that are usually hiddden or inaccessible, or to give/deny apps permissions or features, or, as in the screenshot to change certain keys values. This allows you to change the environment and settings of the app on launch, and revert them on app close.

You can see all the current settings by using adb:

adb shell settings list [ global | secure | system ]

Or in termux with shizuku:

settings list [ global | secure | system ]

In the following screenshot I enter the shell using shizuku (rish) list global settings and find keys with adb. I change the value of adb_wifi_enabled (wirelese debugging) from 0 to 1 and set {1} as the default value. Then I list again to show the change.

This is what geto is doing. But it assigns it to the action of launching/closing an app. While doing it manually via terminal set those values system wide.

Sometimes, though, you may want a system wide change (like if you want to change the accent colors or theme from RAINBOW to VIBRANT).

(There are other configs and properties you can viewed and modify using other commands. (in shell try

cmd -l 

For a list of services. Some have user modable options. Be careful. If you don't know, don't touch. Every setting can be searched . there are hundreds or thousands .)