The systems the parent cites are single-mode. You can run 160 wavelengths through a single-mode fiber. This is done in optical transport systems for "long haul"

The systems the parent cites are single-mode. You can run 160 wavelengths through a single-mode fiber. This is done in optical transport systems for "long haul". The wavelengths are close together just far enough apart to accommodate the bandwidth needed for each channel. Multimode fiber is used for short distances after demultiplexing the wavelengths, typically in data centers. Although I would not say that 100 Gb/s on a single wavelentgh is "basic" at this point in time.