Deflation, not inflation, steals from the poor and gives to the rich. Deflation depresses wages and increases the value of assets (including outstanding debts! rich people use debt, poor people have debt.)
I'd argue both hurt poor people. Wage growth typically lags behind inflation.
poor people either aren't in debt (because no one will lend to them), or have debt on such short timescales or high interest rates that inflation has a negligible effect on the real value of their indebtedness.