I noticed that there were tags that were present in the latest version that were not present here. Perhaps more specifically, the tag c:shears was what alerted me to this.

c:shears is not added or populated by AutoTag, it's part of Fabric API's convention tags module:
https://github.com/FabricMC/fabric/blob/1.20.1/fabric-convention-tags-v1/src/generated/resources/data/c/tags/items/shears.json