That’s not true if you’re talking about well-made men’s dress shoes. In that market, the best shoes are the best entirely because of materials and workmanship. Brand mainly indicates the level of quality you should expect as a buyer. Also, the brand can’t serve much of a social signaling function because usually trademarks aren’t visible and designs are traditional.
That makes sense, but since you're mostly paying for expert labor, decreases in the cost of the raw materials won't affect the price much.