> I would be happy with any random 1000x improvement or two you've encountered over the years

I already provided two examples. See: https://news.ycombinator.com/item?id=22980487

"Two which I have personally worked in are autonomous spacecraft control and chip design."

> I don't really buy the regular 10x improvement either though (as in something achieved by other means than different form of formatting).

Why exclude a "different form of formatting"? That phrase is sufficiently vague that it could potentially refer to just about anything.

> something you can only express concisely in lisp (because of prefix notation? macros? I don't know) and it is bound to be 10x verbose mess in a c-like lang.

You are still fundamentally misunderstanding the claim. It is not that there is anything that can be done in Lisp that could not in principle be done in a c-like language with a comparable number of keystrokes. The history of c-like languages is one of continual refinement and adding features that do precisely this.

The difference is that in Lisp if you need a feature that isn't already there you don't need to wait 30 years for standards committees and compiler writers to catch up. All you need to do is take ten minutes to write a macro.