It reduced my productivity when I used it.
Between having a slightly faster and slightly customized version of google vs. being sent down misleading rabbit holes, the latter won out.
I found a few niche use cases where it proved useful but it was all out of proportion to the hype.
I've paired with other people who were bullish about LLMs using them and witnessed them falling down rabbit holes. I found the whole experience bizarre - it was like seeing a new "social reality" take precedence over what was happening in front of our eyes. Computer says yes.
I have found GPT-4 very useful for understanding concepts and solving specific problems in programming, science, maths, psychology, relationships, and producing creative writing, by having conversations with it, going back and forth deeper into these topics. But I would never use it as an API reference. Raise it up to the conceptual level and you will be surprised at what it is capable of.
What makes you think this, I'm assuming you've tried gpt-4? I've personally gotten a lot of productivity out of it. Assuming it gets a lot better, I don't see how it's not going to minimally become an indispensable tool, and at maximum completely transform the future of humanity.