I would say it's debatable as to whether YouTube has been harmful. I think many aren't a fan of the licensing changes and other experience elements, but maybe those would have happened anyway.
I agree w/ Pixar to some extent, but it seems they have seen a slight decline in quality recently (Cars 2, Monsters University, Brave). I think particularly, they may be looking for more opportunities to exploit previous franchises vs. making quality films. Cars 2 was the best example of this, as was evident by the mounds of merchandise on store shelves following the release.
Again, both of these are debatable, but I still don't think you can say in either case that the acquisition was favorable to the consumer.
I think youtube wouldn't have managed to continue operations without a company like google stepping in. It was running massive bandwidth costs and did not have the ad network in place to monetize.
I think what helps explain this image is that it's likely everything before Cars 2 was already in development prior to the acquisition. Pixar seems to have lost some of their magic, however Disney is certainly stepping up their game.
The aesthetic divide between them is shrinking. I did not like Wreck It Ralph though. Not at all.
Pixar is still making (some) good movies under Disney.
I'm sure there are more examples.