So most apps once opened, keep running and takes up memory even if android container or system is restarted. I think a stricter policy like most android phones as default would be better. Only apps that get exception to battery optimization should keep running in background.
For now I set stronger battery optimization for apps from android settings. It'd be nice to be able to kill android apps also from usage or in the android apps list show memory usage of apps as well. Now I have to look at usage and android section of apps list to kill an app.