Some would say, this was their idea all the time, push forward and substitute Touch ID by a superior technology, face Id.
Some would say that they weren’t able to create a Touch ID sensor that worked behind the oled screen, so they had to pull another alternative.
Some would say that they wanted to implement both technologies but they weren’t able to do it on proper time.
Either way, Touch ID is dead and even If, at the present, face Id is not on par (if...) It will evolve to be far superior.
Move on or buy an IPhone 8.
Next year, there probably won’t be new Iphones with Touch ID.