This is a thought provoking question. I didn't miss it, but I didn't read it as irony, I read it as a sort of awe-struck breathlessness on the part of the author... or at least, the slightly emotionally distant (aloof, not really ironic) version of that that the New Yorker is very good at.

The idea of writing this sort of piece about someone whose grand ambitions have not yet been realized is both to make the reader aware of the grandeur of the ambitions, and also to draw a line in the sand so that his accomplishments can be judged later, aided by the glimpse into his unfettered idealism.

This is not a criticism of the New Yorker (I love it). Just a phenomenon of the unique genre of personal profiles that the magazine produces. The same tone would also work if writing about an artisanal butcher in Maine, for example.