Hello Thomas,
Once a Chromebook reaches its AUE date, it will no longer be able to receive software updates from Google, including security updates, bug fixes, and new features. Without these updates, apps and browser extensions may no longer work properly. The Chromebook will also become obsolete and will not be able to be updated through auto-updates or with the USB recovery method.
I am not 100% sure if the app will be removed from your computer’s Chrome browser, I would test by removing a single app before removing all of them.