@mikedev Some developers need labels that are independent entities. Actors will use these (pre-defined) labels to categorize objects, including objects created by other actors.
Hashtags are usually ephemeral and are added by authors themselves.
For example Lemmy is working on a tag system but they don't want to use hashtags https://github.com/LemmyNet/rfcs/blob/main/0004-post-tags.md