I love that article. 5 seconds of Googling shows that Elop didn't actually become CEO of Nokia until the end of 2010, but for some reason the article decides to start half a year earlier, with the sales record of the previous CEO, who was forced out for poor performance. You're reading an article that's more concerned with being a hit piece than the truth.
Another 10 seconds of Googling shows that at the beginning of 2011, Android was the top smartphone OS: http://www.tomsguide.com/us/an...
Elop talked about all this at the beginning of his infamous "burning platform" memo.
Realistically, how would a CEO completely tank a phone OS in like two months? Steve Jobs needed a few years at Apple before his ideas really went from concept to production.