AWS was launched as a fraud (using no amazon infrastructure at the time, they claimed it was built on the reliable services of Amazon.com) and became a success.... so long as you have unlimited investor money to burn you can eventually be successful this way.
But it is a terrible place to work, because outside of the AWS organization you end up working for idiots.
As for the AWS thing ... I joined AWS pretty early in its history and even then we had amazon.com workloads and it was definitely the same infrastructure (data centers, network, operations, etc) as Amazon.com . My first two years I was writing code and building AWS services, while also supporting retail operations and dealing with the order pipeline - and I worked in Infrastructure; things were fairly integrated.
> for every success Amazon has about a hundred failures
This ratio is off, but even if it weren't it's still not a detracting statement. At Amazon, we're allowed to fail sometimes. Try something quickly, iterate, test, and let it die. Google used to be similar, though they've 'streamlined' a bit more lately.
> outside of the AWS organization you end up working for idiots
Never worked for AWS, can't speak for them. But in my org (Fulfillment) I've worked for incredible managers and a few not-so-great ones but never anyone I'd call an idiot. This isn't a place where smooth-talkin' MBAs thrive. If you bullshit and can't back it up with results, you won't last long.
Most of the MBAs I've met at Amazon were for the Operations world anyways. The Pathways program (https://www.amazon.jobs/en/teams/university-mba-graduate) puts new MBA grads into leadership positions at the fulfillment centers and sees what they're made of. Hard work, but if you do well you go really far very fast.
It's no surprise MBAs want to go there. Strategy jobs are some of the most hotly sought after roles -- my wife went to a top tier MBA program and I regularly have to hang out with people she want to school with. They all either have strategy roles or wish they did (minus the one person in finance -- in the SF Bay Area that's just not as cool as strategy). They also tend (with exceptions) to have egos bigger than big, which seems to line up nicely with thinking that the right job for you is to have the ideas while other people implement them. :)