well, sure, that uses a large number of processing cycles for each small operation. But asking a frontier LLM to evaluate a lisp expression is more or less on the same scale (interesting empirical question whether it's more or less). And, if we count operations at the brain neuron level it would take to evaluate one mentally....
I'm sure in the future there will be technology to evaluate simple Lisp expressions in only milliseconds of time, spending mere joules of energy.