These are the same thing. The policy is to remove educational disparity.
Naturally force flows along the path of least resistance - rather than raising everyone up, which is hard, we are simply removing anything difficult from the curriculum, which is much easier (at the expense of actually educating anyone, a goal that nobody cares about much any more).
The easiest way to make equality is to multiply both sides by zero.
Many in teachers' unions don't want to be rated on how badly public schools are doing. It's not all the fault of teachers, granted, but incentives of the union here is not always aligned with the students. Many don't want to hear it, but it needs to be said as a factor.
There are a lot of these initiatives - like Russian math - popping up serving as test cases for how to teach subjects.
I think online programs are injecting some badly needed new energy.
The easiest way to make equality is to multiply both sides by zero.