To be so expansive with the examples, it's called an obfuscation though I get the point of placing the Japanese version within a broader category. Still this has little bearing on the function or application of the shingle making nate. The two nate of mine have never been confused for riving implements in any way - though the double bevel is a good splitter, (not river)- and no self-respecting Japanese shingle maker would go trimming branches with a froe, just the same as I would not with mine, both made specifically for their work, by any stretch of the imagination, so I'll stick to the shingle making comparison as pertinent 'n illustrative, after all in German a froe is a schindelmesser if it's used for shingle making or otherwise and shingle making's probably the most widespread application for these tools I'd wager, with hurdle making occupying a fringe or niche along with the other reasons for want to rive out sections, like greenwood furniture making, or something.
The distinction twixt splitting and riving lies in the matter of controll and the controll gets exercised through the levering action. In the one instance through the addition of a grip mounted perpendicular to the tools blade in the other parallel with it. These claims overstate the importance of configuration Missing the fact that the function is identical, placing the primacy of catigorization over use. OK, if that is your perspective, by all means, you are my guest.
A froe ( in the broad sense ) does occupy a somewhat unique position Implying space for ambiguity rather than emphatic declarations.