I sort of combined Perl Mouse's solution with OP's original attempt where a sort was directly used but eliminated the wrapper sub:

my %hash = ( ... );
my $orderby = "age" # or name, dob, etc
my $direction = "ASC" # or DESC
foreach my $id (
    map
    { $direction eq "DESC" ? reverse @$_ : @$_ }
    [
      sort {
                $hash{$a}{$orderby} <=> $hash{$b}{$orderby}
                ||
                $hash{$a}{$orderby} cmp $hash{$b}{$orderby}
      } keys %hash
    ]
) {
  print "$id - $hash{$id}{$orderby}\n";
} # end-foreach

__END__
# my test script:
perl -le '@x=(1,4,5,2,3,9,6,8,7); $direction="DESC"; print for map { $
+direction eq "DESC" ? reverse @$_ : @$_ } [sort @x] '
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