That's exactly what they do - they explicitly call out this format as replacement to tar and zip at least:
> Most popular solutions like Zip, gzip, tar, RAR, or 7-Zip are near or more than three decades old. While holding value for such a long time (in the computer world) is testimony to their greatness, the work is far from done.
> Pack tries to continue this path as the next step and proposes the next universal choice in the field.