I would be willing to bet that most of them have mitigation strategies in place that they can, at least in part, switch to. They don't use them because they are less cost effective than AWS (or other current providers) but they should be able to switch with relatively little notice.

I believe you, but I would be willing to bet those mitigation strategies are a few unmaintained word documents that would be grossly insufficient if it actually came that far.

I don't see why NetFlix would have to be more paranoid about AWS, then say Apple about Foxconn. Business is business, except at Google.

Netflix is actually pretty well known for its resiliency to AWS outages.