I see a decent productivity boost in my personal projects which extend common technologies to solve more "boring" problems, but struggle to find much gain at work where we're deep in esoteric technologies that LLMs have little to no knowledge of.

Are you also finding gains in the latter cases?

What I've found is that the capabilities of LLMs depend on the problem solving skills of the person writing the prompts. If you know exactly what needs to be done and can translate that into step-by-step prompts it can do pretty much anything, but if you're looking for it actually solve 100% of the problem you're going to run into issues. Which is to say you still need to find the solution but you just have the LLM do the monkey work.