That idea's been around for decades. And it's never been seriously implemented. Maybe it will be, once things are horrible enough, but then it will be too late.
China is only partially on board in terms of concerted action, but they are spending the most amount of money of any country on green energy. You could characterize it as accelerating and turning at the same time. In a way, scaling up and cutting the cost of solar and electric vehicles is arguably the most important thing at the moment, because it increases the degree and speed at which they undercut the current technology. We need to push as many boulders over the top of hills over the next 5-10 years, so that big emissions savings can occur through blunt economics even without pricing in carbon.
A lot of the US is also on board, notably California which on its own is one of the worlds largest economies. And on top of that a lot of important institutions, particularly academic. There is enough to be making progress with. Even the parts of the US which actively refuse to do anything will get dragged along when products are made cheaper.
That is good news, for sure. But the problem is "covered by the scheme". And yes, China is gearing up. However, at least some of the emission cuts are offset by imports from China. Do the estimates that you've cited account for that?
Bottom line, the Mauna Loa CO2 record tells us that not much has changed since 2000.[0] Not even over the past five years.[1] Except for a jump in 2016, anyway. And OK, maybe a hint of a slowdown in the past year.
California Cap-and-Trade Legislative Analysis 2017
Auctions Have Generated $4.4 Billion in State
Revenue. ARB has conducted 17 quarterly cap-andtrade
auctions since November 2012—generating
roughly $4.4 billion in state revenue. Beginning
January 1, 2015, transportation and natural gas fuel
suppliers were required to obtain allowances for
the GHG emissions associated with the combustion
of their fuels. Since transportation fuel suppliers
are not given free allowances, the number of stateauctioned
allowances increased substantially in
2015—resulting in auctions raising significantly
higher amounts of state revenue.
Except in one of the worlds largest economies: https://en.wikipedia.org/wiki/European_Union_Emission_Tradin..., along with some other advanced economies: https://en.wikipedia.org/wiki/Kyoto_Protocol#International_E...
In first world nations it's mostly just the US (and a few other smaller nations) dragging their heels.