> Android supports region locking and has some region locked apps too, it appears, according to Google.

No, Android does not support region locking. Neither does iOS. (Technically, you can make your app look at the SIM country and exit if it's not what you want, but nobody does this.) App stores on those platforms support region locking. The problem the author is highlighting is that you can't just get the ipk and install it directly to get around the app store's restrictions like you can on most Android phones.