I ended up making one of these mostly by accident as well.
I needed a bike to live on the indoor trainer, so got a 26" MTB frame, bought a set of gravel bars and then raided my parts bin for 10sp Ultegtra STI's & rear derailleur, MTB crank with 44T (all I could get my hands on), rigid steel fork and the rest of the drive train and used an old front wheel to complete. So all in all it cost me about R1k to put together. Bargain!
I liked how it looked though, so the idea started brewing in my head about turning it into a working bike. The fork and frame had disc brake mounts so it was possible to do it. Then my wife bought a new road bike with disc brakes which came with a spare set of wheels which I immediately stole to see if they would work, and they did! Clearance is perfect with 38C tyres. And to get around the braking issue, TRP make a hydraulic caliper which is cable operated, so its all normal cables until the caliper. Neat and powerful.