> A dark fibre network or simply dark network is a privately operated optical fiber network that is run directly by its operator over dark fibre leased or purchased from another supplier. This is in contrast to purchasing bandwidth or leased line capacity on an existing network. Dark fibre networks may be used for private networking, or as Internet access or infrastructure.
They GP talked about "installing a decent amount of dark fiber" not running a network over someone else's unused fiber, which I think is the "network" part of your quote.
> A dark fibre network or simply dark network is a privately operated optical fiber network that is run directly by its operator over dark fibre leased or purchased from another supplier. This is in contrast to purchasing bandwidth or leased line capacity on an existing network. Dark fibre networks may be used for private networking, or as Internet access or infrastructure.