The confusion is that Perl effectively closes over the value of the variable, not a reference to the variable.

sub make_funcs {
    my $val = shift;
   (sub {$val * $val},
    sub {$val++})
}

my($f3, $i3) = make_funcs(3);  
my($f5, $i5) = make_funcs(5);  

say $f3->();  
say $f5->();  
$i3->();  
say $f3->();  
say $f5->();  

__END__
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