First, 78° is wide enough for a lens intended to be used wide-open. Fewer elements LF lenses are made to be used well stopped down; a lens fast not only for focusing but for shooting too, has to imply way more elements for decent sharpness.
Second, the above does look as a retrofocus (though not as much retrofocus as SLR lenses are of course). The front negative element is perhaps more powerful then the 2nd and 3rd positive ones combined. Besides, the 4th concentric cemented group is probably negative, too. Retrofocus design in often useful in non-SLR cameras also.
And BTW generally, more elements do not mean better performance. In lens design, substituting two or more elements for a single one is actually a cheaper Ersatz for meticulously recalculating the original few-element design to perfection (go compare Tamron to Leitz for example). The results are mediocre but way way cheaper and faster to obtain... Well, sharpness can be OK nevertheless but out of focus rendition of a multi-stand-alone-elements lens is almost never good, as messing with more and more elements means introducing more and more higher-order aberrations, and those are far from being any good for the resulting picture beauty.
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