No, Smart Fibres technology is based on measuring the frequency of the reflection from fibre Bragg grating sensors. When there is attenuation in an optical fibre (whether through hydrogen darkening, poor connectors, fibre bending or any other effect) there is no change in the frequency of the light that passes through it. That means the signal of the Smart Fibres technology is not affected. Indeed, Smart Fibres interrogators are designed to compensate for attenuation in the fibre by automatically applying gain of up to 27 dB, individually on the reflection of each FBG within the system. So, for a Smart Fibres system, as long as the light gets through the data quality is maintained.
Hydrogen darkening and other means of attenuation mainly affect distributed temperature and strain systems based on measuring the amplitude of Raman or Brillouin backscattered light. Here, any change in amplitude can have a significant impact in the measurement quality. A simple comparison is frequency modulation (FM) vs. amplitude modulation (AM) in radio communications.