In the unboxing therapy video, the iPhone shows an earlier time AFTER the bend than during the bend. During the bending, the iPhone says 2:26 pm, while after the bending it says 1:59 pm.
It could very well be the phone was actually bent with much greater force before we saw him bend it with his bare hands. This could've made the material weaker and easier to manipulate with less force. At any rate, it does not add to the credibility of this video.
These videos are all about getting views. If you look at the TLD video, the iPhone barely bends which is not surprising since the video is sponsored by the case maker Spigen.
What we need is a professional, independent investigation on multiple phones that measures just how much force is needed to deform the phone until the change is permanent. Right now it's just a bunch of scary campfire stories as far as we're concerned.