Is there much of a market for medium-detail processes? We have the desktop/server/workstation/smartphone market using the very smallest detail processes, with maybe some categories using the previous-generation node. Then we have the embedded market which is everything from cheap-as-dirt 350nm microcontrollers to 28nm ARM chips. Nobody really wants the five-years-ago chips, the currently 18-22nm node. They're too expensive to buy by the million and not shiny enough to compete against the newest stuff.
There are plenty of market for in between 28nm to 12nm node. It is simply a natural progression between Cost, Features, Performance and Economics of Chips. Especially when they are the last few nodes before you move up to EUV.
A10 / T2 used in many of the Apple Appliance are 16nm, along with dozens of WiFi, Modem, Ethernet Controller, ASIC / FPGA etc. These are easily 100M unit a year. As long as the cost benefits fits their volume they will move to next node.
