User blog comment:MisterWoodhouse/Creating new wikis on the Unified Community Platform/@comment-24361909-20200303203008/@comment-1807002-20200303205709

I can confirm as someone who has been trying to absorb dead/overlapping wikis of similar/same topics for months that they look are a bunch of factors. Even if it is edit dead- it could still be viewer active. I was denied a merge once because it was more viewer active than mine (but that was about 6 months ago) and to try again later if the stats were in my favour. They look at content differences and if you only want to cherry pick from that wiki; they are not keen on deleting user produced content you don't want.

And just last week when staff was considering my request with merging another dead wiki. They very much asking me to message and wait a decent amount of time to try for a fusion collaboration/permission. And ask again later if still no response.

I hope this satisfies some of what you are asking.