Poor article with a huge unfounded bias. Article fails to demonstrate how 500m less revenue constitutes backfiring, the country can afford it just fine. If anything this is better as it reduces wealth inequality.
Personally I would demand of "reducing wealth inequality" that it makes everyone richer, not poorer. If this is the sort of equality you want ... what's the goal? Let's all be dirt poor?
By all goals set for this tax when introducing it, it's a failure. It did not change anything, made everyone poorer and reduced the state's ability to do anything about it.