Carbon pricing systems have shown that they're successful in reducing emissions. Every emission or tonne of emissions reduced has a real impact, in terms of both avoided climate impacts and avoided health impacts from air pollution. The most recent Intergovernmental Panel on Climate Change report, the 1.5 report, shows us just how much of a difference 0.5°C in average warming can cause.
On January 30th, 2019. See this statement in context.