I specifically looked at Stamford when I wrote that. Tokyo is in the 350-600sq ft range by the article. You can currently get a fairly spartan 600 sq ft in Stamford for the price listed (one vacancy). That's more than the average the article cites, but in the same range.

After all, you'd have to compare the outskirts of Stamford with the outsirkts of Tokyo.

The theoretical travel time might be an hour, but we can't realistically compare the travel time variances between MetroNorth and Japanese trains.

Going to Stamford is maybe like 1 hour, with frequent catastrophic delays and problems, such that we can maybe model it as like 1.5hr +/- 20 minutes, whereas an hour on a Japanese train is like 1.01hr +/- 30 seconds.

Wildly different user experiences.

And in the other direction, an hour out of Penn Station can get you about halfway across northern NJ even with extensive train traffic.