The Relevance of Brecht: High Points and Low

On one hand, the main thrust of Brecht’s dramaturgy seems almost beside the point in an age of cynical reason. What critical edge can we ascribe to the estrangement effect when Brechtian techniques are used to sell kitchen sponges on TV? On the other hand, a contemporary performance of Saint Joan of the Stockyards speaks clearly to our age, not just to a bygone era of monopoly capital and liberal sincerity. Have we been missing something in Brecht that explains the paradox?