It’s fascinating to consider this from the Creator’s side of things. I know that YouTube has never actually been profitable in any of their fiscal years, so I imagine that they would need to start charging more as well. But perhaps a larger issue is that Media companies (agencies) are charged (incentivized really) with delivering the largest audiences at the lowest CPM. So if YouTube started charging more, advertisers would simply shift budgets to Facebook, or Twitter, or Instagram or Snapchat, or even AOL Video and Yahoo. I would argue that the blame truly lies with the industry as a whole, not so much YouTube, in regards to keeping the CPM’s low. So the argument of “too much inventory” is still valid, just on a scale that encompasses all online video ads, not just YouTube.