Probaby that he didn't "choose" it over Abraham, for example, but that he just started using his legal name from birth.
"Other adjustments at City were less pronounced. I became Andrew instead of Avrohom Yehuda."
Point is, he claims to have "chosen" Andrew over his real name to assimilate better into school. But out of school he is still using Andrew, as evidenced by the name on the article.
The issue here, beyond the choice of *what* name to use, and I believe this is what
@Freddie was getting at (though he can speak for himself) is why would he feel the need to use his legal name in the first place, and why is he being dishonest about it?
And yes, he's being dishonest - intentionally or not:
If he started using it out of school as well, the change was far more pronounced than he's letting off.
If he always used his legal name, what change is he referring to in the article?
To judge him like this feels gross. But when you write such a piece and imply that others should follow your example, you are opening yourself up for analysis to see if the affects of the school had on you were maybe not quite as rosy as you made out.