Adding dates to content like a blog post provides value when the content can best be understood by the relationship with when the content was created. Otherwise having a ‘Posted on: yyyy-mm-dd’ does little more than to signal there is activity here and that you are the kind of person that writes regularly.
Evergreen content does not need a date to be understood and it’s context is derived by the content around it (content as topology rather than content as serialization). In fact, a heuristic for telling if a piece of content is evergreen would be to remove the date and see if it still makes sense to someone in the future.
See also:
- Reverse chronological content took over the web talks about the pitfalls of websites defaulting to a single sort order