Most people don't plan their lives out like you are suggesting. They take opportunities as they come, and build their life as it comes along. He attended Yale, liked America, stayed, worked and built a life for 15 years. I find this reasonable, and consider it unrealistic to expect him to, at any point during that time, to just abandon his current life because he might not be able to stay.
It's one thing to attend university for 4 years, get a job and then head home. Quite another thing to base/commit your entire life/career in the US without a clear path to citizenship.
I'm not saying the author should "suck it up" but rather it seems many take this risk, knowing the dangers and therefore shouldn't be surprised or shocked to eventually have to leave (given a gap in employment)
People like the author and me are not surprised, but rather disappointed (and sad).
Also due to the duration of time involved changes in the law can both screw you up or make it possible. Can you predict what the legal system will be like 6 years down the road ?