Venezuelan crude exports are declining sharply as new U.S. sanctions push the country’s oil industry closer to collapse, threatening a bigger impact on global markets than many experts anticipated, people familiar with the matter say. Oil storage is filling up in the country as President Nicolás Maduro’s regime struggles to line up buyers for the crude shipments that make up his government’s only real source of income. The U.S. restrictions, aimed at redirecting crude revenue to opposition leader Juan Guaidó,…