Α good question would be : Why is there dysregulation of phospholipid metabolism in the first place ? Is it a consequence of mitochondrial dysfunction?
To me, the lack of certain phospholipids could come down to a simple secondary nutrient deficiency, as is often seen in the case of oxidative stress or chronic inflammation. As an example, oxidative stress might lead to a lack of methyl donors, which would disrupt the activity of Phosphatidyl-ethanolamine methyl-transferase (PEMT) in the liver, compromising the CDP-ethanolamine pathway to the eventual synthesis of phosphatidyl-choline. In this case, the observed lack of certain phospholipids would also be seen in other conditions with oxidative stress or chronic inflammation.