User blog comment:MisterWoodhouse/The first migrations to the Unified Community Platform/@comment-33603920-20201002230045/@comment-1038387-20201003151407

Wikitext is a thing in MediaWiki software; Discussions doesn't use that. Forums were using MediaWiki for a thing it wasn't meant for, which created a monster under the hood that held back overall updates and just collected more and more issues.