I fundamentally disagree with your conclusion. Could BC do better? Sure, but the tax is not a failure. The environmental movement can’t afford to let the perfect be an enemy of the good if necessary progress is to be made. Sticking it to poor and rural communities is both unjust and will only guarantee carbon pricing never happens.
Comparing 2008 carbon emissions in BC to present total levels, there has been no real overall increase. In fact, there’s been a slight decline based on the latest data I’ve seen. However, when you adjust for population and economic growth during that same period per capita emissions have actually steadily declined. I don’t think it’s entirely fair to cite BC’s overall emissions as evidence of failure without also taking into account the fact the province has also seen rapid population growth that under normal conditions would have likely pushed BC’s total emissions significantly higher.
Finally, classical linear economics assumes that overall revenue neutrality erases the incentive to conserve, but this overlooks the fact that the tax is only revenue neutral in the aggregate. Heavy polluters still pay more. In addition, it is the upfront prices at the pump or store counter that has by far the greatest psychological impact when it comes to consumption decisions, not the promise of future refunds.