Solutions to bypass it would be to create a symlink to the former path, to add it in -I directive when calling perl, add it to the $LIB (not $PATH variable)

$LIB is not a perl thing or a perlbrew thing

The simplest solution to not having perlbrew break in the future, is to have one of your perlbrew perls as the first perl in the path, so when you type perl or perlbrew its the one from your home directory that runs, so when you upgrade your OS and your system perl (os perl), your home directory perlbrew installed perl is untouched and works the same