I wish all software products would do that. Chat applications are like a busy town square where everybody is yelling into the crowd and important information doesn't survive the moment, while a discussion forum will eventually grow into a public library which preserves information and makes it searchable (assuming that search engines have access to the information of course).
Huh? Have you not used the search feature in Slack or Discord? Whether it's a forum or a chat, the data structure is largely the same, especially with Slack/Discord as they have threads.
Come on. Discord or slack is like a forum where you have every post ever made on a topic in a single thread, 92,000 pages long. Sure, you can use search, but the nature of chat means that once you find one message (say, where a question was asked) you have to then skim through other discussions also going on at the time — often many of them — wondering if anyone answered the question, or if the discussion might continue after each interruption.
It’s okay for some applications I guess, but it’s the worst replacement for a forum, wiki, or knowledge base I’ve ever seen.