Sure we have Wi-Fi and TV screens on the headrests of many newer planes but what would be really nice is to be able to fly from Dallas to New York in, say, an hour.
While you might think a market exists for such demand, my Google search revealed the following answer on Quora.com:
Peter Kämpf, Trained aerospace engineer
Updated Apr 22 2016
Originally Answered: Can planes fly faster?
Airliners can fly a little faster but would consume disproportionally more fuel, and the most economical speed is actually a little slower than what most of them are designed for.
Going supersonic adds a new type of drag (called wave drag) and drives down fuel economy. The Concorde was an excellent design but could not compete once the oil price became a real factor after 1973. Therefore, commercial flying is still subsonic and will stay so for the foreseeable future.
The second generation of jet airliners (Boeing 707, DC-8) were designed for Mach 0.85. The increase in fuel prices since then would have driven down the most economical speed, but advances in aerodynamics have compensated for that and the maximum cruise Mach number is still at Mach 0.85. Please note that we are talking about the maximum cruise Mach number; all airliners will fly more economically at slightly lower Mach numbers between 0.78 and 0.82. Flying any faster than that will drive up drag disproportionally.
Now we need to define efficiency. For airliners this is haul capacity per time and can be expressed by the product of payload, range and speed. When none of the three constituents can be changed without making the product more costly to achieve, you have reached the point of best efficiency.
It appears we will remain at the status quo for a while which reminds me of one of my favorite quotes from Laurence Peter:
Nothing much happens until the status quo becomes more painful than change.
Source : http://www.tylerpaper.com/TP-Blogs/302841/nelson-clydes-is-it-just-me-time-travel-going-supersonic