In the "it works"* case: It's not even close. I did the math at some point (but I encourage you to talk it through with the LLM of your choice, there is obviously a lot of things to consider and weigh).

Anyhow, my research summary: Individual humans are so fucking expensive to train and upkeep (and this includes everything from before womb, where another human already limits their ability to work) You retain ~zero knowledge after death and start all over again for another measly 15 years of effective, productive work. Model training/r&d in relation, when deployed and used at scale, rounds to zero, even with the current retraining regime.

*Of course, the ratio can go to negative infinite if one assumes that models are doing 0 useful work currently and never will