He did mention in the middle of the article, he's buying private insurance:

"My living expenses were rapidly eating away at my personal savings. Between my $3.3k/month Manhattan apartment, private health insurance, food, and utilities, it cost $6-7k per month just to sustain myself."

If my experience (in California) is anything close, it costs somewhere around $500/mo for a single person his age. (If you have a spouse it gets up to around $1000/mo, and with kid(s) it goes up to about $1500/mo) This was 2013-2016 numbers, and was also with Covered California, not sure if that makes it any cheaper.