The comments on this particular video are actually pretty interesting.  They border on the realm where theological discussion meets philosophical and scientific discussion.

Commenter IA says:

Most of these videos are pretty good, but this one is really good.  If, after seeing this, you’re wondering why we haven’t all been enslaved by sentient aliens, it probably means that (i) FTL is impossible, and (ii) sentient life at our level takes a similar amount of time to develop on other planets, and we are in the lead, or (iii) we aren’t yet developed to any level where we are worth bothering.

Commenter “Magnesium” has a far out and really intelligent theory:

There are more options than the ones you listed. Here is another option: advanced civilizations have learned to travel faster than light and control their biology and environment to such a degree that their intelligence skyrocketed and their need for resources minimized. And considering the universe is so old, and considering the high likelihood that many other more advanced races have existed for a very long time, a kind of social order among various advanced races has been established, and that social order includes non-aggression against other sentient beings. Why? Because technology, science and the abundance of resources in the universe which can be used for most efficiently in utilization.

We hope you like the video.