I don't mean to go all cui bono, but the company behind the study[] has a remarkably consistent knack for getting the message out in mainstream publications (HBR, Bloomberg, Economist) that the world's economies must learn English or fall behind. That may or may not be true, but the company's business is "language training" in 116 countries, seemingly with a focus on teaching English.

[]https://en.wikipedia.org/wiki/EF_Education_First