I haven't done anything ^ extreme or cool on that level, but I'm pretty introverted and don't necessarily get excited externally too much. It could be plausible that he's introverted as well and doesn't go crazy like some people. My parents often were upset with me because they didn't think I liked what they got me for my birthday, christmas, etc. but on the inside I really was happy/excited.
So all that to say, everyone handles events differently and it's hard to have a set guideline for how people act.
My thoughts too. There does just doesn't seem to be enough adrenalin in his system. If it's real, he doesn't understand the risk he just exposed himself too. At those heights, any sort of malfunction would probably see him dead.
Not to be a jerk, both those three videos you posted don't seem to encompass exactly what happened here.
I'm not saying it's a real video but everyone's reaction is different towards any event. I don't think this can be counted as proof against the 'realness' of the video.
So all that to say, everyone handles events differently and it's hard to have a set guideline for how people act.