Of course they ignore the evidence. Supply side is faith-based, as it always will be.They ignore extensive evidence of what — in fact — drives economic growth and stability and can deliver improvements in living standards.
Instead, they reflect supply-side economics, as trumpeted by Arthur Laffer, who was a paid consultant for the Brownback plan and a volunteer cheerleader for the Trump tax cuts. Laffer’s theory of growth has been a foundation for economic policies since the 1980s.