This is also household income, not personal income. Last I checked, the 1% mark for a single guy was roughly $192K/year, and for a household it was about $388K. If his spouse makes an equal amount, he could very well be in the 1%.

Plus he mentions in the article (technically, in a comment) that his quarter-million figure includes insurance, 401k, discounted ESPP, and stock (which has a 1-year vest). It's not at all unbelievable that his actual salary could be as "low" as $150k.