Hey! I am one of the author of the article. This is not really an abstraction on top of Ansible. Just a tool to generate configuration files from templates as Ansible is pretty bad at this (slow, not providing a line number in case of problem, variable lookup quite rigid). Then, it's just regular Ansible using network modules to deploy the result.

We push the opinion you need to manage the whole configuration to avoid getting out-of-sync with their expected state or putting the state inside your device. Once you are able to manage the whole configuration, the things you describe are possible: propagate a VLAN, adding IP to an access-list, etc. The other way around is not true.