C.A.R. (Tony) Hoare said of Algol 60 that it was such a good language that it was not only an improvement on its predecessors, but an improvement on nearly all its successors as well. The spirit of that statement rings true for me[1], and I feel that the same could equally be said of many Lisps, especially when I think of things like read/write, CLOS, streams, conditions, (delimited) continuations, hygienic macros, etc. Common Lisp has been virtually static for over 30 years[2] not because it's "behind the times", but because it was so far ahead of the times that everything else is still playing catch-up!
[1]: I feel as though Algol 60 was, with few exceptions, the best language available until around the mid-to-late 80s.
[2]: Not to mention that it really hasn't been totally static: now we've got ASDF, QuickLisp, {U,C}FFI, CLIM, SLIME, etc. And loads of libraries.
Algol 60 was largely superseded in the mid-1960s.
I don't think that you've been paying attention to recent Common Lisp libraries or recent lisps. Lisp has never stopped evolving and continues to take ideas from other languages.