this works but it uses a regex and eval

#!/usr/bin/env perl

package Deblessify;
use strictures 2;
use feature 'say';
use Data::Dumper;
use YAML::Tiny;
use Moo;
use MooseX::MungeHas 'is_rw';

# attrs
has 'abc';
has 'def';
has 'foo';
has 'bar';
has 'name';

run();

sub run
{
    my $self = __PACKAGE__->new;
    $self->abc({aaa => 123, bbb => 456,});
    $self->def([qw/123 456 789 abc def ghi jkl mno/]);
    $self->foo('foo bar baz xyzzy');
    $self->bar(123.456789);
    $self->name('testfile');
    $self->deblessify;
}

sub deblessify
{
    my ($self) = @_;

    my $dumpstr = Dumper($self);
    say "dumpstr = $dumpstr";
    $dumpstr =~ s/^(\$VAR.*? =) bless\(/\$deblessed_obj =/;
    $dumpstr =~ s/\s*?},\s+'.*?'\s+\);$/};/;
    say "new str = $dumpstr";
    my $deblessed_obj = '';
    eval $dumpstr;
    say "deblessified obj: $deblessed_obj";
    my $yaml = YAML::Tiny->new($deblessed_obj);
    my $filename = $self->name . ".yaml";
    $yaml->write($filename);
}

1;
__END__
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