As far as I can tell, the vast majority of academic projects (particularly those of undergrads) have worked on narrow AI, which this is supposedly not.

That's definitely a reasonable assessment. I dialed all those estimates down by about an order of magnitude from when I started writing that point as I thought through just how unusual attempting general AI is. But over sixty years and hundreds of institutions where one might get a sufficiently solid background in CS to implement something big, there are going to be lots of unusual people trying things out.