Apples & Oranges
I don't think certificate pinning or O/S checks are intended to prevent reverse engineering. They're there to try and ensure that someone isn't doing something nasty to the end-user. (e.g. fake Subway's servers)
Without hardware assistance, I believe it's quite hard to truly prevent reverse engineering of a software. All you can do is insert traps to slow people down,
At the end of the day, the app developers took some time and trouble to make reasonable efforts to protect the service they provide and they were slapped down by someone seeking some publicity.
Biting the hand that feeds IT
