Increases to minimum wage increases costs of goods but at a lower rate than the increase of buying capacity. This can be demonstrated on the following spreadsheet that can be edited for new calculations (yellow cells only, other cells are auto calculated from them).
Buying capacity = cost of goods / wage. As wage increases, cost of goods increases by labour portion of goods x wage increase as %. New buying capacity = new cost of goods / new wage. In other words, your new buying capacity has increased by the difference of non labour costs of goods and services. - Important Question; are all costs labour costs? If so; minimum wage doesn't matter - unless sourced from outside that pool of labour, if some costs aren't labour costs; minimum wage does matter.
Increase to minimum wage might result in loss of job opportunities; which in turn reduces that person's buying capacity.
The formula in the referenced spreadsheet to calculate additional buying power is not well known algorithm and can't be relied upon to make definite conclusions. Also, the approach fails to take into account number of units produced. As such, the argument about buying capacity can't be reliably used.