There really probably isn't that much interest in the overall market. Most people don't really bat an eye at brands like Yamaha and Ibanez and just see them as the "beginner" or affordable brand.
Plus there's also an issue of false information, which Yamaha themselves have spread, like with the nonexistent BB600 that Peter Hook claims was his first Yamaha bass - such a bass does not exist, yet Yamaha themselves wrote about the BB600 in various articles talking about Peter Hook's history with Yamaha. One would have to be very careful when writing it as to not include incorrect information.