That doesn't make sense because salaries are a current expense, not a capital expense to be amortized. And why 5 years? The work a software engineer does may be outdated in a year or two. Only certain legacy applications are around for 5 years.
The amortization time period is supposed to match the usefulness of the item purchased. Basically, software engineers are an ongoing expense, not R&D.
They made their own content because Hulu was a partnership between 4 different content companies intended to screw Netflix out of money.