It drives me crazy when people send mass company emails with, for example, new policy or forms attached, and don't post them elsewhere. New hires only see them if someone remembers they exist and forwards them, plus it's impossible to figure out current state without spending a bunch of time playing email archeologist.
We've been remote founders and employees in numerous distributed startups, and have always found the same issue, the noisy nature of chat/Slack and lossy nature of email necessitates a 3rd place to keep the important decisions, announcements and history of the company.
Lots of companies use wikis and forum software for this, and those can work, but we're betting that a dedicated solution can work better.
The email is sent as a notification that the content has been added, updated or moved.
Email should ideally serve as a notification system and a lossy communication system where things you want to retain need to be backed up somewhere else.
The nice thing wth email is that being an open eco system there are a lot of integrations that are supported easily.