> under the same conditions

That's a very interesting question. When comparing wildly different computing machines, how to make a fair comparison?

At least two criteria comes in mind: the volume and the energy consumption.

Indeed we can safely assume that more volume and more energy leads to more computation power. For example, it is not fair to compare a 10m^3 room filled with computers with 10cm^3 computer. The same goes with the number of kilowhat-hours used.

Thinking further on those two criteria for GPUs and humans, we could also consider the access to energy and volume. First, energy access for machines has dramatically increased since the industrial revolution. Second, volume access for machines has also increased since the beginning of the mass production. In particular, creating one cube meter of new GPUs is faster than giving birth to a new human.

tldr: fair comparison of two machines should take into account their volume and their energy consumption. On the other hand, this might be mitigated by how fast a machine can increase its volume, and what is its bandwidth for energy consumption.