FWIW, I've tried running tlmgr update with NYTProf (https://metacpan.org/pod/Devel::NYTProf) (as in /usr/local/bin/perl -d:NYTProf tlmgr.pl ...) I saw no especially low-hanging fruit :(. Maybe someone would like to try running the installer that way and see if there is anything that jumps out. Or I will at some point, but not soon. --thanks, karl.