Forums are one of the features that the rival storefront Steam currently offers to devs on that platform, so the decision is another notable difference between the two PC game stores.
Players replying to Epic CEO Tim Sweeney's tweets on the subject are torn about the decision, but for devs the lack of forums on the Epic Store makes for one less platform to moderate and means they can lead with and promote their existing communities if they choose to host their games to the Epic Games Store.
Sweeney discussed that decision and others in a handful of tweets about the Epic Games Store this week. Many of the things he discussed have already been mentioned on the storefront’s public Trello roadmap, like mod support and others, but he also had a few interesting things to say about what features aren’t being planned for the platform.
Namely, Sweeney says Epic doesn’t have plans to build in-store game forums into the Epic Games Store at this point. Instead, he says the company encourages devs to have and link to external forums on sites like Reddit on the store listing for their game. It’s something Epic practices itself with Fortnite's own r/FortniteBR subreddit and Sweeney notes that they “encourage forums … that are independent of stores and platforms.”
In another notable departure from Steam, Sweeney also says that there are no plans to develop a trading metagame a la Steam Trading Cards, though many other features players have come to expect of digital platforms like gifting and achievements are already on the roadmap.