The Rein Ruhr industrial was back in German hands by 1925. Germany just wasn't allowed to station troops there, but it was fully in German control otherwise.
Germany instituted one of the most protectionist trade schemes ever done in an industrialized nation and the depression was over by 1935. Again, why did the great depression end in Germany but drag on forever in America and the UK? It wasn't protectionism, it was the elimination of the debt bubble.