I think the issue is not so much the question of how long it takes someone to learn a tool, but the repeated cost you get get from using it on a day to day basis. (I'd still be super impressed if you had storeconfigs and the spaceship operator nailed in a day!)
For instance, I worked for a major computer vendor doing an OpenStack deployment, and watched a simple deployment there suck up 20 developers for six months, where all of that time was in writing automation content.
Repeated hammering out of dependency ordering issues, coupled with the non-fail-fast behavior, and having to trace down where variables came from turned us into automation tool jockeys, so we couldn't focus on architecture and development. The project barely had deployments extending beyond 5 nodes in the end from all of the complexity.
Ansible already existed at this point, but it provided major fuel for me doubling down efforts into expanding it. The goal here is not just the basic language primatives, but making it really easy to find things as you have a large deployment, and making it really easy to skim/audit even if you aren't a really smart programmer.
That all being said, Puppet deserves major credit for pioneering a lot of concepts and revising CFEngine.
While Ansible aims to be a cleaner config tool, but also focuses on application deployment and higher level orchestration on top, so you get some capabilities not found in those other chains (like really slick rolling update support).