I suspect that getting HI to change its terminology will be about as successful as getting the kamis to change the way they make knives. Every once in a while someone proposes micarta or G10 handles. That gets batted around for a thread or two and goes nowhere.
The terminology is not really a problem. Anyone who's been around this subforum more than a couple of days learns many things about khukuris, including what HI means by "full-tang" and chiruwa. New people will tend to have many questions, and tang-type is only one of them. New people ask questions and old people answer them. It might seem repetitive, but that's the price we pay for having new people come around. The answer is not to change the HI terminology to conform to what new people are used to from an entirely different context. Many of the knife models have names that only make sense from a Nepalese historical or linguistic background, such as Ang Khola, or ASTK, or Bag Bahraib, etc. HI could call them all Bowies, but that would simply undermine the tradition for no real reason.
Handle type is not the only way in which HI terminology differs from what is common on Bladeforums. Most postings outside the HI subforum use "length" to mean blade length. In the HI world, "length" means overall length. It makes more sense when you're dealing with bent-blade designs. I have a 22" Hanshee knife that would be 25" if you straightened out the blade. Of course then it would be a sword, not a Hanshee.
Another difference involves weight. I've noticed that on the Bladeforums Exchange many postings, probably a majority, do not provide the weight. That's probably because most non-HI knives are not nearly as heavy as HI knives, so the weight is less of an issue. By contrast, if you are buying an HI heavy chopper, there's a huge difference between a 32 oz blade and a 48 oz blade. For some people the latter would be completely unusable in the field. Yangdu always gives the weight of a DOTD.
It's a matter of the terminology being adapted to the culture and physical characteristics of the HI traditional designs.