Most forums were awful phpbb nonsense where it was impossible to find the information you wanted. Search always required logging in and the only interface for very long threads was paging through them 10 badly laid out posts at a time.
No thank you.
Of course modern forums are better. Disqus is ok, and D's forum software is arguably the best thing to come out of the D project.
In any case Discord is not a replacement for forums; it's a replacement for IRC.
