The measurement problem here is real. "10x faster" compared to what exactly? Your best day or your average? First-time implementation or refactoring familiar code?
I've noticed my own results vary wildly depending on whether I'm working in a domain where the LLM has seen thousands of similar examples (standard CRUD stuff, common API patterns) versus anything slightly novel or domain-specific. In the former case, it genuinely saves time. In the latter, I spend more time debugging hallucinated approaches than I would have spent just writing it myself.
The atrophy point is interesting though. I wonder if it's less about losing skills and more about never developing them in the first place. Junior developers who lean heavily on these tools might never build the intuition that comes from debugging your own mistakes for years.