But there has got to be a reason why they gave these things a different name
. I thought MAYBE the propfans/UDF are "fans" and the turboprops are "props"? (again, no satisfactory source on the internet that explains where you draw the line between a prop and a fan).
What's in a name? The important thing is knowing what the actual arrangement looks like.
An Airbus official back in 1985, when high fuel prices had raised the hysteria level to such heights that some of these machines were actually made, was attributed the description 'a load of bananas whirling around'.
We have become so good at designing fancy swept prop blades that the cruise speeds they can achieve at a reasonable SFC are approaching those of subsonic turbofans, and the A400M is a living example.
Supposedly there's a long way to go yet. There's still another generation of big fan engine improvements before the ductless approach is required. The A400 props do have the look of the future tho.
30 years have gone by since the last foray which says something.