It’s a fair metric IMO.

We typically judge super computers in FLOPS, floating-point-operations/sec.

We don’t take into account any of the compute power required to keep it powered, keep it cool, operate peripherals, etc., even if that is happening in the background. Heck, FLOPs doesn’t even really measure memory, storage, power, number of cores, clock speed, architecture, or any other useful attributes of a computer.

This is just one metric.