Issue with updmap-sys use of symlinks in cross platform installation

[John Collins]

Background:
I'm using TeX Live 2024 (and previous versions also) hosted on macOS, but with 
a platform added for windows.  (That's so that I can share the installation 
with a VM running Windows, to let me do testing of latexmk, without the need 
for yet another installation of TeXLive on the VM.)

With this set up, there are a couple of symlinks generated under 
texmf-var/fonts: texmf-var/fonts/map/pdftex/updmap/pdftex.map and 
texmf-var/fonts/map/dvips/updmap/psfonts.map  These symlinks prevent pdflatex, 
lualatex, xelatex, dvips and presumably others from working correctly under 
some situations, when they are run from Windows.  I get error messages about 
Permission denied for those map files.

I didn't find a mention of this issue in the TeXLive documentation.

I have corrected the problem simply by running 'sudo updmap-sys --copy' after 
an update by tlmgr, and that appears to cause no trouble.

Suggestion:
If I understand the code correctly, updmap.pl uses copy instead of symlinks 
when it detects that it is being run under Windows, or that the file system 
does not support symlinks, or that the --copy option is used.  I would like to 
propose that it also use copy when the windows platform is installed, even when 
updmap.pl is being run under another OS.

Are there any significant downsides to this?

Perhaps there are other situations when copy is needed instead of making 
symlinks, but updmap-sys does not detect the need.

John Collins