I think that you are working it a little to hard. There is no "utf-8", but there is ":utf8". I always use ":encoding(UTF-8)", just to be safe.

Here's what I did: If you use the new_from_url method, then it will call LWP::UserAgent for you.

#!/usr/bin/perl

use strict;
use warnings;
use HTML::TreeBuilder 5 -weak;

my $url
    = 'http://buyingguide.winemag.com/catalog/peju-1998-reserve-cabern
+et-sauvignon-napa-rutherford';

my $tree = HTML::TreeBuilder->new_from_url( $url );
$tree->parse_content( $url ); 
    
my $review_et = $tree->look_down('itemprop', 'reviewBody');

binmode STDOUT, ":encoding(UTF-8)";
print $review_et->as_text;
$tree->delete;
[download]