system
A chat on subreddit /r/wallstreetbets
human
He probably graduated undergrad and law school early and went big law making around $180k to start. It goes up each year and the bonus can be around $50k a year if you hit your hour targets. Its definitely plausible if he was in a low cost of living area and lived frugally. 
  
 Edit: just read elsewhere in the thread he is in a low cost of living metro. I'd bet Austin, TX.

gpt
And/or parents paid for a chunk of the education so his 'debt' wasn't that high.