64% get tenure according to http://www.sciencemag.org.libproxy.mit.edu/content/335/6070/... at least. Median time to exit the tenure track? 7 to 10 years depending on the area.
So now imagine this. You work as a PhD student for 6 years, as a postdoc for 2-3, as a faculty member for 7 years. And at the end (you're just about 40) someone flips a coin. Either you get tenure, or you beat it and get nothing. Along the way your industry peers have outearned you by hundreds of thousands of dollars by this point.
So yes. The situation is that bleak and the article is not overstating its point.
Along the way you have to keep in mind that things are only getting worse. Grant funding is much harder to get today than it was 10 years ago. Tenure rates are much lower than they were 10 years ago. So if you're planning on a career in science you have to factor in the fact that the situation you will face when you come up for tenure will likely be far worse than the already-poor statistics above indicate.