You are under the assumption that 'efficiency' means resource efficiency. That is untrue. Exhibit A is how convoluted our current system is with our non-renewables. Replacing people with machines won't fix that.

Efficiency is celebrating the fact that you can drop your expensive annual costs and the liability of employing humans to conduct your business. People are expensive and demand things like rights and benefits. Machines can be had with a purchase/lease and maintenance costs.

Machines won't negotiate or get a lawyer. That's efficiency.

Meanwhile, we'll strip the earth to build these machines in the name of efficiency while more of the population is made useless and left to rot by an economy that functions without them.