Debian (and thus Ubuntu) has full support for automated installs since the 90's. It's built into `dpkg` since forever. That include saving or generating answer to install time questions, PXE deployment, ghosting, CloudInit and everything. Then stuff like Ansible/Puppet have been automating deployment for a long time too. They might have added yet another way of doing it, but full stack deployment automation has been there for as long as Ubuntu existed.