I think that's correct, because when you purchase anything on which the GST is charged, you pay the amount, whatever it is. It gets reduced a little, and that's a small help, but across the board it's much more difficult for people living in poverty. The tax they pay is a much greater percentage of what they actually have to spend than when you make a better income.
I think reducing the GST is certainly helpful. Anything that makes things cost less is useful, but in the grand scheme of things it's not going to make a huge difference. It certainly doesn't substitute for a strategy to reduce poverty by bringing all these large trends together.