@pat-1
should be
@arr1-1
and can be written as
$#arr1

The following should be a bit faster and much more memory efficient (but not as neat):

my @all;
push(@all, [ $arr1[$_], $arr2[$_], $arr3[$_] ])
   foreach 0..$#arr1;
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Even faster?

my @all;
$#all = $#arr1;
$all[$_] = [ $arr1[$_], $arr2[$_], $arr3[$_] ]
   foreach 0..$#arr1;
[download]