Two points of contention I have with your point that wireless has less latency than optical glass:
1) You don't operate wireless in a vacuum. There's all kinds of potential obstructions to the signal, including any physical objects
2) Even if wireless as a medium itself has less latency, it requires far more relay points to travel comparable distances to fiber, which introduces far more latency than the medium itself
On 2, it is true, but often wireless operators have their relays connected to fiber. (Except for very remote area coverage, but that's another matter than replacing the cable company monopoly)
1) You don't operate wireless in a vacuum. There's all kinds of potential obstructions to the signal, including any physical objects 2) Even if wireless as a medium itself has less latency, it requires far more relay points to travel comparable distances to fiber, which introduces far more latency than the medium itself