It's the AWS branding that's confusing. A few things aren't called what they actually are. E.g. Route 53 is actually just DNS. Coming from an Azure background (where things are consistently called what they actually are), I took one look at that mess and noped the fuck out.

It's also not just networking. That bit about failure was really glossed over, given that it's the biggest problem that you have to contend with in the cloud. If you are running hundreds of machines, shit fails frequently. You not only have to design your infrastructure to deal with that, but your coding style becomes ridiculously defensive. Not a real (but simple) example: to move something from one inventory slot to another, you effectively remove it from the first slot and then add it to the second. What happens if the server crashes (bug or hardware failure) between removing the item and adding it? What if your database server disappears for a few seconds? There is even a mathematical theory that deals with this stuff - it's crazy difficult.

Mad props to the team.