It sounds so arrogant.

Yes, agreed. I think arrogance is an attitude, which exists whether or not one is right or wrong. It's one of the things I don't agree with about this video.
Another being that we haven't entirely explained Alchemy, Big Five and DSM disorders -- at least not in an articulated sense, although I think the groundwork is there for them to be framed as sub-phenomenon to CT.
This video was all made in one afternoon and was originally a parody , for those who are wondering. Don't worry I haven't actually lost it, lol. There is perhaps some truth in this video though, that is not covered by me in my native (Alpha) personality. For instance:

Beta Ethics

If we as a group here have really come across a discovery of this magnitude, like.. even if I were to die today, where does that leave our responsibility? Lets forget humility and modesty for second, and think about the ethics of withholding information. Imagine research for a cure for a disease was found and it was kept under wraps.
One could argue CT has been unethical in delaying itself, in not taking more initiative to correct the many misdiagnoses the world is being given. The children being prescribed medication, the infantile understanding of psychology we're still stuck in, but more chiefly -- the tarrying of moving the world's consciousness forward.
This is something I learned from my Beta (Ni+Fe) friends. Alphas hesitate, while Betas follow through. Alphas see their hesitation as a virtue, for democracy, while Betas can see the same action as a sin. And the difference is that Beta's Ni can hone in on what "truth" there already is, and even if the details are not all in place, the vision is right enough and the ethics (Fe) are important enough to follow through with.
This is why Betas can be revolutionaries. It may be the case that they over-exert their confidence, and describe 'closure' where the is still room for ambiguity, but in doing so the are honoring what is known. If we know 85% of the truth of something, and it's in need of some world-wide application, then waiting for that 15% before speaking up is not right. They're already there, and if you understand where 'there' is, their actions make total sense.
So I actually understand Beta Gurus better now, from a human place. At least, I can see how they may be motivated by noble drives, even if they can come across as know-it-all, manipulative and self-obsessed to other quadrants.
It's with that in mind that I made this video. Partly also cuz I think we could use some more Beta energy/"attitude" in CT. Indeed we could use more from all the quadrants.
So even if CT is not at 100% yet, it's already more correct than whatever other options we have out there atm, and that needn't be understated.