Honest question: If the author "had come to America to attend Yale." didn't they also research the requirements for citizenship or an extended stay? Did they decide the benefits outweigh the cons or did they just "hope" things would work out? Maybe they made the decision after attending Yale - was this decision not well informed? I think criticism of the immigration system is warranted and valid, just that potential…
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.