Why is that? Why has the Community user "stolen" the spot as author of the tag?
The creator of a tag is not the creator of the related tag wiki: The creator of a tag is the first user who used it in a question, and so far it is not reported in any place. (There is a feature request about showing who created the tag, though.)
What you see in the history of a tag wiki is the creator of the tag wiki. You can only suggest edits for the tag wiki, with the reputation you have. If the tag wiki didn't exist before, then the Community user creates it for you.