The concept that AI will be many times human intelligence is result of biases. The microprocessors went from 4 bit to 64 or more bits and speed went from MHz to GHz. It may not be possible extrapolate the progress of microprocessors in the case of intelligence.
You have no more basis for claiming this than AI reseachers have for claiming the opposite. More research is required, and it will be a well spent effort if the probability of a bad outcome in AI development is nonzero.
