What functionality is missing? What is unsatisfying with the current situation?

Currently, the discussion boards offer a useful tool for play-by-post roleplaying, but in order to find out what has happened in the game recently, you have to log in to World Anvil first. If players do not develop a habit of checking an additional site, gameplay may be slow and require the GM or other players to manually send reminders separately.

How does this feature request address the current situation?

I saw that there was an earlier request for direct emails, but thet was turned down for very reasonable reasons, as World Anvil is understandably concerned with being seen as spam.

However, i see that World Anvil is able to use RSS feeds to notify followers of World Updates, so i thought they might be an option for providing external notifications for new forum topics and new forum posts. Players could subscribe to RSS for an overall forum, a category, and/or a topic, and use the RSS reader of their choice (which includes some e-mail programs) to get notified when things are happening in their games.

What are other uses for this feature request?

Aside from roleplaying forums, this could allow people to keep track of activity in other world discussions and expand the use of the discussion boards as tools in worldbuilding, collaboration, and roleplaying.