Tesla’s European sales crisis deepened in April. Why it matters: European customers have been turning away from the brand after CEO Elon Musk became an outspoken ally of President Trump. By the numbers: Tesla sales fell 81% year-over-year in Sweden, 74% in the Netherlands, 67% in Denmark and 62% in the U.K., according to industry association figures on April registrations compiled by Bloomberg. They also fell 59% in France, 55% in Belgium, 46%…