As you imply yourself, $2.23B of depreciation even when fully realized leaves them with over $8B in earnings. So depreciation isn't the main cause of the HXM negative cash flow. I looked at 10 year cash flow and it seems to me the cause is their inventory is growing much too rapidly. That eats up all available cash while reducing their cost of goods and raising their earnings.
You would want to study that and understand it very well and be sure to look at comparable companies to get a sense of how others handle inventory.
Their return on equity is just okay at a little under 15% and is coming down. Their return on assets has come way down under 5%. So business model shows deterioration over time.