That reminds me of Reddit's endlessly repeated questions. Possibly there's a large audience that refuses to look for an answer prior to asking a question? Almost an expectation of free "service".
That might result in a preference for Discord. With a refusal to research it's free developer tech support.
Well, that would explain why "users" prefer it, but not why "developers" prefer it.
I'm not involved in any large open source project, but I'd expect I'd rather not answer the same question over and over. I'd therefore choose a platform which doesn't incite that behavior.
I see a lot of communities on Discord will use bots that recognize keywords from commonly repeated questions. The bot then spits out the answer typically associated with that question. It seems to be somewhat helpful that way.
I've also seen similar done but with a bit of manual intervention. Some kind of support/mod person will see a repeated question and use a command to trigger a canned answer to that commonly asked question.
Or say they want log files, they would trigger a canned message from a bot explaining how a user can get that info.
In some sense it almost works like a support chat on a webpage. The support agents have canned responses and can link out to support articles.
That might result in a preference for Discord. With a refusal to research it's free developer tech support.