If you really want to convince people that human intelligence is the minimum of general intelligence possible given the laws of physics then in my opinion you have to provide some examples of other evolutionary designs that are very inefficient compared to their technological counterparts.

E. g. trying to estimate how fast the first animal that walked on land could run and comparing that with how fast the currently fastest animal on land can run, how fast the fastest robot with legs can run and how fast the fastest car can "run"?