Spill is only useful where your eyes actually make use of the photons that are flying through the air.
The only moment where a very broad spill is useful is for close-up work or the like. In medium distances or the typical "it is dark outside" scenario a broad spill will just vanish into nothing, especiall when in contrast to a hot hotspot.
This way, the SF optic does not waste photons in limiting the spill angle, which is one reason for the exceptional performance of those lights outside, th eother being the broad hotspot making a cone of light that illuminates your field of vision just fine.
There is actually plenty of spill present around the spot, it fades quickly into nothing though.
Of course I admit that this optic won't solve all problems of the illumination world
... and all is subjective.
I would not read a book with it, for example. I would not hunt white walls either.
It is outside where this one shines.
bernie