You can get flexibility or simplicity, pick your poison. Not all solutions have the same needs so the idea that there exists a single, simple out of the box solution for every problem is naive at best.
Yes and they were advocating for simplicity as a possible (starting) way for Meta.
Except the complexity wasn't created for the sake of creating complexity - it exists for a reason. You can go the simple route if you happen to be brand new to virtual infrastructure management. The problem is you're going to quickly outgrow your solution and then what? Besides, if you want simple you can go with Wix, Wordpress, or Digital Ocean.
I'm sure that at least some of the complexity in AWS exists because they can't go back and refactor their offerings when so many users depend on it.
“A monad is just a monoid in the category of endofunctors, what's the problem?”