So why have so few people heard or thought of it?
I suspect people don’t think about it because it’s just not the way we perceive the world. We innately feel that we can know everything if we just work hard enough. It took me decades of reflection before the BC conjecture hit me over the head and started to sink in.
The reason most people have never heard of the conjecture is that it’s a non-starter. It’s an interesting observation, but then what do you do with it? Various philosophers have touched on the idea: John Locke, Immanuel Kant, Noam Chomsky, Colin McGinn, Thomas Nagel, and John Searle are among those I’m aware of. If anyone is familiar with other scholars I’d love to hear of them. But once the point is made, there’s no way to develop it.
In my book I don’t develop the logical argument more than anyone else has, although I do offer my own perspectives. But the BC conjecture helped provide a framework for many of the perplexing conundrums we face in mathematics and the sciences. And the conundrums provide evidentiary support for the conjecture.