Can you explain what those examples are supposed to demonstrate?

What I got out of it is that the naive rule is:

1) the match operator compares references.

Therefore, if you smart match @arr ~~ 2, you are doing this:

my @arr = (10, 20, 30);

my $aref = \@arr;
say $aref;   #ARRAY(0x1810e90)

0x1810e90 ~~ 2

--output:--
NOPE!
[download]

However, the naive rule breaks down here:

my @a = (10, 20, 30);
my @b = (10, 20, 30);

my $aref = \@a;
my $bref = \@b;

say $aref;
say $bref;

--output:--
ARRAY(0x1810e90)
ARRAY(0x181ace0)

#yet...

say @a ~~ @b ? 'yes' : 'no';

--output:--
yes
[download]

So you can't really say that the smart operator is comparing references, otherwise @a and @b would not match.