Completely outside of the productivity debate, offloading cognitive tasks to LLMs leaves you less practiced in them and less ready to do them when the LLM isn't available. When you have to delegate only certain tasks to the LLM for financial reasons, you may find yourself very frustrated.
Google's TurboQuant might help address this, but it also might just widen the gap even further.
I am far on the skeptic edge when it comes to the generative AI side of ML tools though, so do take my opinion with that weight.