Issue there is the ability to trace out the brain networks accurately. We're getting closer. Once we're in the ~0.5 micron scanning range, things will get VERY interesting.

I believe we've already mapped some invertebrate brain, maybe 250 neurons.

We've made pretty good progress. But the same problem that plagues explainabilty of ANN's rears its ugly head in neuroscience.

Low level descriptions provide shockingly little insight into high level behavior.

Yes, but also your original question was about how much people care, so questioning the amount of progress is at best a weird tangent.