I think rollbacks shouldn't count towards posts becoming Community Wiki posts.
If there is no change in content, the post was not generated by the community, but keeps being written by the original poster. If different users suggest and rollback edits, happen it twice and any single edit (e.g. to fix the issue) will make the post CW, for no justified reason.
Strongly related : Does / should a rollback count as an edit toward community wiki?, I assume (oh so lightly…) it's being one year without activity shows something of a consensus, so I upgrade the main tag. (Also, I feel like it didn't receive enough attention, but I lack the rep to drop a bounty and still keep commenting.)
Less related : SO is too eager to turn my edited answers into Community Wiki. Status-declined, and many upvotes. I like the second most upvoted answer for the solutions it proposes.