Google's John Mueller said on Reddit that links from Wikipedia not only have no SEO value but also those links "will do nothing for your site" from a Google search perspective. In fact, John said all you are doing is "creating extra work for the Wikipedia maintainers who will remove your link drops."
Back in January 2007 Wikipedia nofollowed all external links to try to reduce spam on the site. Well, I am not sure if it reduced spam or not but the links probably do not pass any link weight in terms of Google's algorithm.
John said on Reddit "Randomly dropping a link into Wikipedia has no SEO value and will do nothing for your site. All you're doing is creating extra work for the Wikipedia maintainers who will remove your link drops. It's a waste of your time and theirs. Do something that's useful in the long term for your site instead, build something of persistent value."
So not only is it a waste of your time, you are also wasting the time of the Wikipedia editors.
I should note, that DuckDuckGo appears to count links from Wikipedia. :)
Forum discussion at Reddit.
