Okay, it took me some time to reach a point in video where I can make informed comment. I'll type as a I listen to the rest.
There is perhaps a debate that is going on POW and POS but I fail to see it as debate because for me POW represents how human beings have traditionally seen wealth (to be earned by labor) while POS represents modern aspect of money(stored wealth need not be in circulation for it to produce more).
Both are competing systems which until DPOS were seemed in a reasonable equilibrium. DPOS changed all that. The fear of concentration of wealth with time in a POS based platform is now gone because of DPOS.
Delegation is obviously the key advantage the POS needed over POW that it got with Bitshares, Steemit and now EOS. I am still learning and thus might be wrongs on some counts.
With EOS the DPOS has become even more mature and we have something that could possibly outlast all similar previous projects. The vote buying aspect............the definition of vote buying as you stated in the video does not apply to this DAC distribution. On the other hand if the team provides incentive for people to choose them - then that is a fair play in a free market. Rest would depend on how people judge the team based on their future work.