We never had a situation where we could outsource unique problem solving at all levels.
You say "Putting software into those roles loses us nothing that is human." but you can have LLM produce design at all levels. I can't think of anything LLM cannot replace humans with, except maybe physical labor, which requires good robotics precision, that we haven't perfected yet.
The main part that's missing however, is that the nature of linguistics (and the core to LLMs' success) is that LLMs are wiring together useful concepts that humans spent thousands of years polishing and relating to one another in speech.
Language has been the code behind all human thought, understanding, emotions, and innovation. It's what enables LLMs to work. LLMs don't _understand_ words, they connect them together usefully, which works because humans mapped useful composable words to useful composable concepts.
And if you think about how human thinking and consciousness is often attributed to language in the first place (not clear if we even would be conscious without language), a lot of human is being delegated.
I'm not sure what to do about it, but I find your kind of explanation incredibly reductive.