Netflix’s challenges and its competitors

Please do some research on Netflix and answer this question by USING the framework I uploaded:
QUESTION: What are the biggest challenges in our current competitive landscape? Which competitors should we be most concerned about, and how should we respond to them?

This question focus on: 1. biggest challenges; 2. competitors; 3. how to respond.
For this three dimensions, please please please use frameworks!!! (file named frameworks).
I have uploaded the case in 2017 (named case 2 Netflix), but while answering this question, we need to use the most recent information. I also upload a Netflix in 2019, please do more researches if you need.