> I doubt that LLMs will ever beat humans at this, but if LLMs can be proven to be good at point 2, then point 3 alone will not save human physicians.

Agree with your division but I'm baffled by this argument. If humans are better than machines at point 3 and can also use a machine to do point 2, then unless they have particularly terrible biases against taking point 2 data into account they're going to be strictly better than machines alone. Doctors have costs, but they're costs people/society are generally willing to underwrite, and misdiagnosis also has costs...