Bear in mind that prominent stocks like Amazon don't trade in their value, they trade on perceived future value and settle where that perceived value crosses with the markets risk tolerance.

Amazon has, and will continue, upward because they are capable of breaking into new markets at scale. Unlike Netflix which is quickly approaching market saturation, Amazon has virtually unbounded potential to invade untouched markets as they are currently doing with postal and produce. The result is that we can't see where Amazon's revenue will finally plateau. What we do know is that AWS profits make them extremely resilliant to taking losses in these other markets but at the same time highly vulnerable to competition from other providers like Google.

Fyi google has the better product, but it's better because it puts the kind of people who decide which to use out of work. So industry hasn't flipped yet. When they do expect Amazon to take a big hit.