It's mainly done based on how much the average WWE fan would know them really. The fact Hokuto's even on that list at all when they could've gone with the other half of that couple who arguably had a much stronger run in America is pretty cool regardless.
I'm not sure Kensuke would have qualified for the list. WWE was pretty tight with their definition of who didn't perform on their cards. Kensuke probably 'worked' for WWE when he teamed with Hawk as Power Warrior on joint WWE-All Japan cards. He certainly deserved higher billing than some of those named if he did qualify. Hard to say.
Same thing could be said about Jaguar Yokota. Does her working against Wendy Richter in Japan when the WWWF women were touring Japan count? Defending the AJW title against Wendy means 'working' for WWWF? Such a tough call when reviewing this list. At least Hokuto clearly never worked a WWE card or worked against a touring WWE wrestler.
Seems like WWE was trying to spread the wealth a little and include other regions besides Japan on this list. Someone like Billy Robinson probably appeared once or twice in his entire career in WWE. Same with an Otto Wanz. But that disqualifies them. Imagine if Ric Flair had stayed in NWA/WCW the whole time but was disqualified from the list because of his 2 MSG appearances early in his career when he beat two jobbers?
Hard to know how they really put together the list.
At least Hokuto made it; I'd have thrown a fit is she didn't!