I cannot imagine how that would work. It’s not the topic that is a wiki but the individual post. If you select topics, the information about which post should become a wiki is missing.
Do you expect that many topics where the first post isn’t a wiki but you want it to be one? I didn’t expect bulk select was needed. Perhaps I am underestimating how many topics are moved to the community wiki. I thought it would be less than one per week.
Would you return topics only when the first post is a wiki or when any post in the topic is a wiki? Are only topics with no wiki posts “not wikis”, or are all topics with posts that aren’t wikis “not wikis”?
I am not a fan of wasting my option to flag a post for unimportant stuff like that. Since I can flag a post only once, I like to keep that for cases where I really need moderator attention. Making something a wiki is not urgent.
But I will be delighted to send a separate PM.