I don't think Kona were specifically going for "The Retro Look" when designing this, more that they realised there was gap in the market for what is ostensibly, a low volw volume, bespoke steel hardtail.
There is a difference between Retro Look and Retro Tech. It may LOOK retro, but thats only on account of it being steel, and therefor having more regular tubing than say, the Scanadium 26" Cindercones with their formed square-round tubing profile.
Its a 29" (modern/fashionable), Singlespeed/Sliding dropout (modern/fasionable) integrated headset (modern) with skinny tubes and old style graphics
Interestingly, I had no idea that from 2010 onwards, there have been no Explosifs or Kilaueas, other than 1 year as frame only
G