There’s no issue with it, you put a force to any material and it bends or breaks, it’s as simple as that. You can bend spoons, break baseball bats, you can even make dents on your cars with a simply kick.
These electronic devices are not designed for being bent or scratched , it’s not their function and there’s no claim from Apple stating that these iPads are bend proof, waterproof, scratch proof or fool proof....
Unless of course Apple would be designing these devices with construction grade steel....but that would just be silly wouldn’t it?