https://bugs.gnu.org/44605
https://git.savannah.gnu.org/cgit/libtool.git/commit/?id=9e8c882517082fe5755f2524d23efb02f1522490

macOS Big Sur is 11.0, Darwin 20, after a long line of 10.X releases.
macOS Monterey is 12.0.
--- configure
+++ configure
@@ -8121,7 +8121,7 @@
 	  _lt_dar_allow_undefined='${wl}-undefined ${wl}dynamic_lookup' ;;
 	10.[012][,.]*)
 	  _lt_dar_allow_undefined='${wl}-flat_namespace ${wl}-undefined ${wl}suppress' ;;
-	10.*)
+	1[0-9].*)
 	  _lt_dar_allow_undefined='${wl}-undefined ${wl}dynamic_lookup' ;;
       esac
     ;;