I can only speculate, but the main researchers are now working on other stuff, like e.g. Anthropic. As to why they switched, I don’t know. Maybe they were not making progress fast enough or Anthropic’s mission seemed more important?
However, at least Chris Olah believes this is still a tractable and important direction, see the recent RFP by him for Open Phil.
I wasn’t aware that the circuits approached was abandoned. Do you know why they abandoned it?
I can only speculate, but the main researchers are now working on other stuff, like e.g. Anthropic. As to why they switched, I don’t know. Maybe they were not making progress fast enough or Anthropic’s mission seemed more important?
However, at least Chris Olah believes this is still a tractable and important direction, see the recent RFP by him for Open Phil.