Your graph model lack the aspect of increasing complexity. As you traverse the graph every available node gets increasingly more distant. In some areas of the graph less so than others, a good heuristic function not only identifies a single shortest path, but also dense areas of possible value in the graph.
The question is if blind speed scales quicker then distances grow.
That's true, and I guess the reason why we're building so many datacenters is to answer the question how far exactly will blind speed take us, assuming that we fail to make substantial improvements to AI architecture.
The question is if blind speed scales quicker then distances grow.