User blog comment:MisterWoodhouse/Creating new wikis on the Unified Community Platform/@comment-24361909-20200303203008/@comment-24155515-20200303215906

"they are not keen on deleting user produced content you don't want."

IIRC when a similar wiki to the one I admin was merged with ours, I specifically asked if I'd have to keep content from their wiki that didn't overlap with ours and I think it was mentioned that I didn't have to but for all I know that meant "you can delete it when it gets here". It didn't end up mattering, though, since the overlap was total and so their articles basically went into the ether when the merge happened.