Optics also have signal integrity issues. In practice OSNR and SNR limit optics. Cutting the fiber still breaks it. Small vibrations also affect the signal's phase.
SNR is obviously an issue for any communication system, however fiber attenuation is orders of magnitude lower than coax.
The bigger issues in this case would be mode-dispersion, considering that they are going through "imaging" fibres, i.e. different spatial components of the light walking off to each other causing temporal spread of the pulses until they overlap and you can't distinguish 1's and 0's.
That said all of that is irrelevant to what the previous speaker said, vibration induced phase variation as an impairment. Thats just not an issue, vibrations are way too slow to impair optical comms signals.