NYC has had very low attendance for the Mets, Yankees, Giants and Dodgers. Maybe in that sport it's about winning in NYC.
Other teams, other sports in NY or around the country not so much.
Fenway park would have sold out every game in 2005 if they had 55,000 seats. For the same high prices.
IMO that Professor using Fenway and its "reduced capacity" implies it was done deliberately. Instead the team played in an 11,000 seat stadium and in 1912 27,000 seat Fenway park opened. It's capacity has increased over the years. Just like Wrigley field. The principle should not be named after Fenway.
If you want to say new Yankee stadium and Citi was deliberate, that's a different scenario.