Currently, the various texlive font packages create fonts.dir/fonts.scale using
mkfontdir/mkfontscale.

This is quite pointless:

- the font packages go into /usr/share/fonts/texlive-<package>/, but this is
outside the X server font path, which is (see /var/log/Xorg.0.log)
 [191632.294] (==) FontPath set to:
        /usr/share/fonts/misc:unscaled,
        /usr/share/fonts/Type1/,
        /usr/share/fonts/100dpi:unscaled,
        /usr/share/fonts/75dpi:unscaled,
        /usr/share/fonts/ghostscript/,
        /usr/share/fonts/cyrillic:unscaled,
        /usr/share/fonts/truetype/,
i.e. to use any of this fonts, the user had to additionally use xset +fp ...
for each package

- this is for the vast majority of programs unnecessary, as it is only needed
for server side font rendering, current programs use client side rendering.