Question

is Matrix an artifact repository

Answer 1

No dear , Matrix is too good

Answer 2

There are two types of artifacts. Releases and Snapshots.  Release Artifact is created by specific release.

They are stable and static. They are considered to be solid. Snapshot Artifacts are generated in a software development project.  

Thus, Matrix may not be directly stated as Artifact Repository. Maven is considered as a build tool by developers.