Seems to me that Shang Chi has fallen out of favor for several reasons, not the least of which is the inability to be able to reprint his adventures because of rights issues surrounding Dr. Fu Manchu.  Marvel no longer has them, so they can't reprint many of the 70s comics where he was a key figure.  No reprints equals a fan base that only really knows him from 30 years ago and maybe a few fans who discovered him via a couple of mini-series and sporadic appearances in Marvel comics since his own series was canceled in 1983. 

I also think that he, more than Iron Fist, is tied to martial arts in such a way that it might be off-putting to anyone just getting to know him.  Iron Fist, no matter his origins, is a superhero.  He has a power and hangs with fellow popular heroes like Luke Cage, Spider-Man, and the like.  Shang Chi, although part of the MU, was always in a bubble.  He didn't work on the outskirts of the MU, for the most part he worked entirely outside of it.  His connection to the popular, iconic characters is extremely limited.  He also often fought with the notion of being in the modern world at all, so he was a reluctant hero at best.

All of this to say that although I'm a fan of the character, and will be getting that figurine, I can see why he's not as big as Iron Fist is today.

New preview from Richard's blog.  Clint, take note, he mentions one of the folks at Eaglemoss is a fan of all the monsters and wants to get them in the collection.  Just in case, you know, you want to start an email campaign or something. 

Sweet!  One of my favorite 70s Marvel characters!  Must own for me.  Great sculpt.