[Feature] Retro on state of package updater to determine the future

This script (while powerful and useful) is a bit all over the place. Following the updates made to the script for the dbt-utils v1.0.0 migration, I would like for us to take a moment to reflect on the state of the script.
- What are the useful components of the script
- What can be repurposed for a future rollout
- Can this be improved in any way
- How can we make this script more modular
- Can we clear up the documentation on how to use the script

The above are just a few ideas I would like to discuss. Following our retro, I hope to outline a few feature tickets on this repo for us to improve and iterate upon this application for future use.

Start by reviewing the package updater script and its current usage documentation. Assess which components are useful, reusable, or candidates for modularization, then record the retro outcomes as concrete follow-up feature tickets. Done means the script's future direction and next improvements are documented.

Written by the indexing model from the issue text.