Have you checked to see if

my @option_config = q"  $UNIQUE_OPT
                        $FORCE_OPT
                        $VERBOSE_OPT
                        $OUTPUT_EXT_OPT=s
                     ";
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No, but doing so shows me that @option_config is equivalent to:

                   [ '  $UNIQUE_OPT
                        $FORCE_OPT
                        $VERBOSE_OPT
                        $OUTPUT_EXT_OPT=s
                     ' ]
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a single element array, complete with the newlines and leading whitespace. Not DWIM.

I'm not sure what your point was...Should q"" interpolate or not? I would suggest it should not, because that would be confusing. But I could live with the argument that it should, because then the behavior of double-quotish strings would be consistent.

On the 3rd hand, things like s"$foo"$bar" behave differently from s'$foo'$bar':

$foo = 'foo';
$bar = 'bar';
$football = 'football';
($x = $football) =~ s"$foo"$bar"; # $x eq 'bartball'
($x = $football) =~ s'$foo'$bar'; # $x eq 'football' (no change)
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My point is, qw is not apparently single-quotish in nature, but it would DWIM to have it double-quotish using double quotes, as with other operators.