The issue isn't the cost of the fiber optic cable itself (I would note that the stuff they use for telecommunications costs a lot more than the shit used for drones) it is the install. It is a lot of man power to go and run cables, be they copper or fiber, to houses particularly if they have to go underground. So companies are reluctant to spend that re-running where a connection already exists.Fiber is so cheap that Hezbollah is using long lines to control drones. I like my copper but as long as fiber has taken it's place then I'm Ok with it.
Wireless now gives an even cheap option to say "but we don't wanna spend money running fiber" since it has zero last mile cost.
It's not the cost of the materials though, always the labor.