What is worrying me more is that we are all stuck on idea of being locked-in to any vendor. Why can't we focus on innovation instead? Take Instagram for e.g. they started with AWS right? Then moved on the real hardware within few weeks (if I remember correctly) after acquisition. I understand, cost of the unseen problems are high, but it might be good idea to remember it also much depends on delivering speed.
Binary compatibility, of millions of third party libraries out there, is the biggest hurdle.
How many years did it take to switch from Python 2.7 to Python 3 ?
AWS lockin is a bigger threat.
I prefer to keep my binaries cloud agnostic and X86 and X64 compatible rather than AWS only code or even ARM binary.
By the way what happened to Amazon phones ?