True, the case would offer resistance no matter the direction that would be bent. But which direction would offer less/more support is key in knowing what would be the best way to handle the device.
As aforementioned, we are no longer looking to see what is the minimal lbs of force needed to bend the device, we are looking to see what is the minimal lbs of force needed to do any damage related to the weaker structural integrity to the device altogether. That would include the screen separating, the glass cracking/shattering etc.
Then it no longer becomes a story of how the weak structure would allow the phone to bend, but how the weak structure would allow the phone to take any damage. That's why its necessary to perform the bend test on both sides of the device!
From what I have seen other phones will bend when the same weight is applied so this si allo a bunch of cr^p!
People who sit on their phones are not expected to remember which direction the screen is when they sit on it!