It's not intended to. It is way outside the scope. But you can easily coordinate transitions on top of Etcd by waiting on key changes.
> Configuration management is as much management order of operations as well as what files should contain what.
Outside of scope. Nothing stops you from using a configuration management engine like Puppet and triggering it on state changes by waiting for Etcd keys. It'd be trivial.
Or use something other than Etcd if those are your needs. But those are not my needs.
For my configuration needs there are exactly no places where I have any interest in the complexity of Puppet, but plenty of places where being able to easily set and query configuration values via a simple REST api that's trivially to access even from a bash script is nice.
You're right that scp can do that. But then you're suddenly in the job of maintaining hairy scripts to push out config changes and ensure they are in sync. So Etcd provides a solution that provides that synchronization without the complexity of far more featureful solutions. To me, that is a feature.
You seem to try to evaluate a handsaw as if it was a chainsaw and give it bad marks for being cumbersome to cut down trees with. Not all of us want to cut down trees.