I dislike using the most commonly offered OAuth providers for sign-in to websites, and would like to see a W option more often...
Topic on Talk:OAuth/For Developers
@Sj, it is challenging as not all WMF accounts have emails linked, which many services require
I see; but do we keep a list of sites / services that do use WM OAauth?
I can think of other reasons why WM OAuth might be more useful for assuring someone isn't a spammer than other common options.