Saved bandwith and faster downloads: Artifactory stores the artifacts that are downloaded from maven central. So if another developer needs the same dependencies they don't need to be downloaded again from maven central but instead they can be delivered from the local artifactory instance.
This makes downloading faster because company networks are usualy ...
If you simply need to build a docker image, I recommend using Kaniko. It allows you to build a docker image without having to expose the docker.sock or running your pods in privileged mode, which introduces potential security vulnerabilities. Per the Kaniko documentation, your spec file would look similar to:
You can deploy docker on same host where you have k3s and then use same technique with docker sock via mounting volume. I.e. this is part of the spec we did for Jenkins on k3s:
- name: dind