On Sat, Jul 26, 2014 at 9:12 AM, Amgine <amgine@wikimedians.ca> wrote:
If we write up a clear ruling on Commons, stating that any STM licenses or other licenses with STM riders are not free and may not be uploaded to commons, this addresses our contributors. A friendly blog article explaining exactly why these are not-free again addresses our community. And both can then be cited by anyone who wants point out to STM  why these should not be promulgated.

The real motivation for providing truly open access would be a Wikipedia policy of preferring such sources when the alternatives are otherwise equally good. How easy it is to find the articles of a given journal online has major effect on its impact factor, and referencing it often in Wikipedia makes it easier to find, both directly, and by external links in the Wikipedia article namespace being a factor in Google rankings.

Apparently there was an attempt back in 2007 to create such policy, but it was abandoned: