As several have pointed out here, the market and the punters have spoken. My first flight from EWR to the UK, to get to Belfast, was on a 747 to London 30 years ago . Right now there are many non stops to the UK and Ireland from NYC area. All on twins. Belfast, Dublin, Glasgow, Edinburgh, Manchester, Cork !! , have a least one non stop. You can call NYC a hub, but most of the destinations outside of London are not.
Another factor is not only what a twin can do , but the old treaties forced airlines to funnel through a national hub. That is no more. Who would have imagined flying from Cork to New York on a 737 even 10 years ago? Another factor no one has mentioned here is landing fees and costs. The more connections, the more someone has to pay. Which is interesting as the non stops are sometimes more expensive than a connecting flight. That tells me airlines can get a premium by saving people time.
The A380 may be a great plane, but it was the wrong bet. One item I read years back was Boeing figured the weight penalty of the second floor with the drag of the bigger fuselage (function of the area, the square of the tube diameter) and the 4 engines was always going to make the double decker an non starter.
Lucky or good, Boeing got it right.
20driver