[jbverschoor]

I think you got your definitions mixed up.

Even the name means: "it's dark, no light, as in no data, because that's what light is in this case"

[freshpots]

https://flexnetworks.ca/what-is-dark-fibre-why-would-i-want-....

It has two meanings. I have heard it most commonly used in reference to private fibre networks.