Board Thread:Support Requests - Getting Technical/@comment-34966228-20190316065139/@comment-24155515-20190316071805

AFAIK you can't. You may be able to enable Wiki-style forums (Forum namespace, DPL forums, work more like talk pages), though you may need to contact staff to do it, depending on their state at your wiki, but you can't enable (or re-enable) forums where Discussions exist instead, and you can't disable Discussions, regardless of what your community might want.

(The wiki I run was switched to Discussions. Neither admin wanted it. DX)