Does YouTube have enough (any) moral compass to avoid making profit in preference to promoting gambling to children?

If they're not fined more than they profit then they're not going to change it.

The incentives of YouTube and Youtubers are aligned against the better interests of society; but that's true of a lot of capitalist activity -- the only way it is going to change is via mass action of the populous (direct action [which might be as simple as changing viewing habits], or legislation).