It would seem that a good portion of society feels the same way that you do.
You are really sort of making my point. Profit and the wants and "needs" of adult viewers come first. What might be best for kids, the ones with no true voice, is thrown by the wayside for a me, me, me, $, $, $ driven society.
YouTube is more important than kids as it stands; no doubt about it.
You are correct, Google/YouTube is not obligated... not any more than I am obligated to stop at a car wreck to help out; or to help an old lady with her groceries. Who knows though, taking some responsibly even though we are not obligate might actually make things a little nicer around here.
I'm not blaming Google/YouTube for the problems of the world and I am not demanding that they do anything. I'm just suggesting that they take some responsibility (even though they are not obligated) and help make the internet even slightly better for kids. They could begin to set a higher standard for the rest of the internet to follow.
As the African proverb goes: "It takes a whole village to raise a child". I'm just asking that Google/YouTube help out.
P.S. Google has some pretty intelligent and heavy hitters on board (and some impressive "revenue"). I'm pretty sure they could come up with a few inspiring solutions.