I remember how hard I tried to add Admob into my first mobile game in 2014. It took me no less than 5 evenings to do this. At first I learnt that there is a commercial Milkman ANE, which cost is around $40. Then found a free Pozirk ANE. Spent much time on integration, struggling with application.xml, bugfixing, and every time when I made changes I had to re-compile the app.
Yesterday I've tested banner integration with FGL Enhance - this took me only 3 minutes, no more. If I wanted to show/hide the banner, then I might need 5 minutes, including adding the connecting drag-and-drop library and writing the code.