Yup, that's exactly it. Even more interesting is the difference between lex and pkg vars:

{  package Pkg;
   sub new     { my ($class, $text) = @_;
                 return bless(\$text, $class); }
   sub DESTROY { my ($self) = @_;
                 print "DESTROY $$self\n"; }
}

my  $lex = Pkg->new('file scope lex var');
our $pkg = Pkg->new('pkg var');
END { print "END\n" }
print("At end of script\n");
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At end of script
DESTROY file scope lex var
END
DESTROY pkg var
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I don't know if the order is unchanging. I wouldn't count on it. Doing our $pkg2 = \$lex; or sub test { $lex } would change the order, for example.