Well, it is technically possible he is at the national average income (not the median wage) and lives in a place where rent is way more affordable than the cities most of HN lives in. U.S. GDP per capita is $55,836.79. That is $44,558 after taxes in Knoxville, TN (I am picking a city, but it could be more extreme, he could work remotely from a rural area in the U.S. or from, say, Belize). This means 25% towards rent is $1163. So, in Knoxville, Zillow says that is a 3 bedroom home.
More realistically, that same amount is a small studio in e.g. Austin, TX.
Now, the trick is that the average income might be $55,836.79, but the median personal income is ~$41,520 [1]
[1] https://en.wikipedia.org/wiki/Personal_income_in_the_United_...