With respect to the Yankees, I was amazed, sitting in the Stadium last October, that the Yanks could not sell out their playoff games. Yes, the weather wasn't so good and it was school nights, but they are excuses. This wasn't a little undersold either, I thought maybe there was approximately 10,000 seats that weren't filled. The Yanks miserable October hitting performance didn't help either. So the Yes ratings don't surprise me all that much.
The 2012 Yanks were not a likable team and Girardi is not an overly popular manager. Fans are really turned off by ARod and his contract has become an albatross for the team. Ticket prices are extremely high. Everything to eat and drink at the stadium starts at $11 it seems. On TV, the Diamond Club seats are always half empty, giving the appearance on TV that support for the team is lackluster, even though the rest of the Stadium may be more jammed.
So, even though the Yanks are "winning", and oh BTW this years team without ARod is thoroughly more likable, there seems to be a malaise in Yankeeland apart from them still putting a good team on the field. In addition to winning , fans do need to support and identify with the players and coaches to some degree.