I don't really know what he meant, with the references to managed code and assembly language in relation to Lisp, but what he actually wrote is wrong when it comes to Common Lisp.
Concrete Example: 7 years ago I couldn't (using available libraries) reliably parse in lisp a DB dump in XML (~8GB), select some records based on a set of calculations, and convert it to CSV. Most libraries insisted on needing the whole document in memory, some libraries leaked like a sieve and caused heap exhaustion, others couldn't handle UTF8. In the end, I could do it python (couple hours to develop and took 45-60 minutes to run), I could do it in java (several hours to develop and ran in ~8min), but I couldn't do it in LISP without writing a custom XML parser or delving into FFI. Maybe it was an abnormal case, maybe not.
I miss macros and the expressiveness; I miss the community; I don't miss the insanity.
These things happened because some people decided to improve CL (both implementations and libraries) instead of using something else.
Good enough is good enough.