While yes we all started on this forum, but if you want to have a conversation with other members/moderators (whether in message or forum replies), Discord is the way to go since you'll be getting notified if anyone is replying to you through DM and the server chat refreshes on real-time, making conversations a lot more smoother. Forum on the other hand is outdated and it'll take a long time for people to get notified when a reply has been made either on direct message or forum replies.

Edit: Plus, Discord is much more user friendly and a lot more bigger than forum, so there's another reason why people prefer it rather than this forum.