I have the latest iphone, but only because I switched carriers and got a good deal. FaceID is fine, but touch ID was way way better... but why don't they put it

I have the latest iphone, but only because I switched carriers and got a good deal. FaceID is fine, but touch ID was way way better... but why don't they put it on the back of the phone like Android phones do? It's so much easier to use it and then you don't have those huge bezels.