I agree; it felt as if the video is trying to browbeat you and force you to apologize. It seemed that the person in the video was himself angry and confused and this made it hard to watch with a "Let's learn a new skill" mindset.
It would have been better if this post could have actually linked to the research about human politeness and how it fits into the instrumental rationality framework. There has been a lot of research on this. A simple google search for 'rationality politeness' reveals a wealth of results.
I think a lot of the tone came from the pacing - the video was edited to mash together a bunch of sentences with minimal breaks in between. This made it much faster than normal speech, so it came across as a barrage of admonitions without allowing time to think about them in between. This was probably not intentional, and the speaker was probably not quite as angry as he sounds.
Now, it is said we all here pride ourselves on our intelligence, rationality, and moral sense. It is also said, however, that we are a fiercely independent bunch, and that we can let this pride of ours get the better of us. There have also been comments that the live communities that appear at meetups provide much more positive interactions than what goes on on this site's discussions; this might merit further investigation.
My point is; we've done a lot of research on how to do proper ethical and metaethical calculations, and on how to achieve self-empowerment and deal with our own akrasia, which is awesome. We've also done some work on matters of gender equality, which is very positive as well. But I haven't seen us do anything about the basic details of human interaction, what one would call "politeness" and "basic human decency". And I think it might be useful if we started tackling these, for our own sakes, that of those who surround us, and that of easing our mission along, which is, as I understand it so far, to save the world (from existential risk (at the hands of (unfriendly and self-modifying) artificial intelligence))).
What inspired me to propose this post was a video I just saw from Hank Green of the famed and fabled vlogbrothers. I hold these two individuals in very high esteem, and I would expect many here to share my feelings about them, on account of their values and sensibilities largely overlapping with ours; namely the sense that intelligence, knowledge and curiosity are awesome, and that intellectuals ought to use their power to help improve themselves and the world around them.
Here it is; I hope you enjoy it