Except that => => (to which I assume you're referring) does not disable leftward stringification by => as ,=> does:

Win8 Strawberry 5.8.9.5 (32)  Thu 06/10/2021  9:48:30
C:\@Work\Perl\monks
>perl -Mstrict -Mwarnings

use Data::Dump qw(dd);

use constant APPLE => 1;

my %heesh = (APPLE => => 'red');
dd \%heesh;

my %hash = (APPLE , => 'red');
dd \%hash;

^Z
{ APPLE => "red" }
{ 1 => "red" }
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Of course a double "fat comma" does not act as the "Winking fat comma". There are four ways to combine two of "fat comma" and "comma". What they have in common is that there is never an additional undef inserted in the list.

Greetings,
-jo

$gryYup$d0ylprbpriprrYpkJl2xyl~rzg??P~5lp2hyl0p$