That headline isn't quite right.
Costs rising?
Netflix has been a cash incinerating machine the last several years. The company burned through more than $3 billion in borrowed money last year, at junk bond interest rates, to be a content creator on a large scale. It has plans to burn through that much or more this year, in an environment in which junk bond issuance has dried up, making it much harder to borrow heavily to the tune of billions of dollars the way Netflix has been able to for the last 3, 4 years.
When you have $9 billion in accumulated debt, and you have locked yourself into obligations to spend another $18 billion or so over the next five years, and you don't generate enough money to actually support that level of spending, your problem isn't that costs have gone up. It's that you were living in la la land all along. It's not a coincidence that "costs rising" only became a problem when the credit markets tightened and there was no market out there for more junk bond issuance.