Delyemination is the death of oligodendrocytes/schwann cell and not neurons per se; The why do we refer to neurodegeneration/neuropathy and neuronal loss?
Reading most published papers on this subject one does need to consider the funding and grant application process. "Neurodegenerative" will have a better chance of passing the funding evaluations and grant boards - while "demyelination" will restrict a lot of the same complex work. Project could be the same design - but different symbols used to explain the process of damage to the brain ultimately resulting in neuron loss often seem to streamline other aspects of the work.