I doubt people say use python simply because it is easy. As Scouting Ninja and Kylotan have said, Python is widely available and good for real-world general purpose tasks.
I still say don't choose a language because it is recommended or powerful. First know what you want to create and learn the language/languages that help you create it. Simple as that.
I chose Python because the Pythonista app on iPad uses Python and it is one of the best ways to learn app development principles (I learned programming with Pythonista). I also now have Swift Playgrounds
Knowing Python also helped me transition to use the Godot Game Engine. I want to learn C# with the Continuous app also (for more understanding of low level concepts).
There is also Codea which uses Lua. I have to learn Ruby for work if I want a promotion (good incentive if I ever heard one). So it's not about which is best. It is about which is most suited for the task at hand. At the end of the day these are just tools.