"If the heavy metal band Anthrax dies of anthrax, that would be poetically tragic, but not ironic.
If a diabetic crosses the street and is run over by a truck carrying insulin, then it's ironic. "
-- Urban Dictionary
I think the African garment you are thinking of might be the dashiki, but those conventionally come in gaudy colours with extra-deep necklines, so you many not find [m]any other plain henley versions like this unless American Apparel / Uniqlo decides to rip it off. But all it takes is a hashtag in the right place to set the ball rolling (#DamnDaniel).
Or I could be totally wrong and it's already trending/commonplace.
It reminds me of the Jil Sander "teardrop" sweater...
The Mr.Porter page is a more significant piece of evidence. Those are major brands -- Lanvin, Common Projects, Margiela, Dries, Dolce & Gabbana, Paul Smith, and Balenciaga -- none of which were featuring or even making slip-on sneakers circa 2011, now all selling practically interchangeable shoes because they expanded into a new category in unison in response to demand.
I've seen things you people wouldn't believe.Attack ships on fire off the shoulder of Orion.I watched C-beams glitter in the dark near the Tannhäuser Gate.All those moments will be lost in time, like tears ... in ... rain.Time to die.(about 75% improvised by Rutger Hauer)Also:From The Naked City (1948)