This is not used (only by itself):

git grep BiblioUtils::Iterator

Koha/BiblioUtils/Iterator.pm:package Koha::BiblioUtils::Iterator;
Koha/BiblioUtils/Iterator.pm:Koha::BiblioUtils::Iterator - iterates over biblios provided by a DBIx::Class::ResultSet
Koha/BiblioUtils/Iterator.pm:  use Koha::BiblioUtils::Iterator;
Koha/BiblioUtils/Iterator.pm:  my $iterator = Koha::BiblioUtils::Iterator->new($rs);
t/db_dependent/Koha/BiblioUtils/Iterator.t:use_ok('Koha::BiblioUtils::Iterator');
t/db_dependent/Koha/BiblioUtils/Iterator.t:my $iterator = Koha::BiblioUtils::Iterator->new($rs, items => 1 );

I know that someone kind of hates Util modules :)

Unfortunately we cannot (yet) remove Koha::BiblioUtils module:

Koha/BiblioUtils.pm:package Koha::BiblioUtils;
Koha/BiblioUtils.pm:Koha::BiblioUtils - contains fundamental biblio-related functions
Koha/BiblioUtils.pm:    my $biblio = Koha::BiblioUtils->new($marc_record, [$biblionumber]);
Koha/BiblioUtils.pm:Creates an instance of C<Koha::BiblioUtils> based on the marc record. If known,
Koha/BiblioUtils.pm:    my $biblio = Koha::BiblioUtils->get_from_biblionumber($biblionumber, %options);
Koha/BiblioUtils.pm:This will give you an instance of L<Koha::BiblioUtils> that is the biblio that
Koha/BiblioUtils.pm:    my $it = Koha::BiblioUtils->get_all_biblios_iterator(%options);
Koha/BiblioUtils.pm:Koha::BiblioUtils of each biblio. This will include the item data.
Koha/BiblioUtils.pm:    my $marc = Koha::BiblioUtils->get_marc_biblio($bibnum, %options);
misc/release_notes/release_notes_22_05_00.html:<li><a href="http://bugs.koha-community.org/bugzilla3/show_bug.cgi?id=29625">[29625]</a> Wrong var name in Koha::BiblioUtils get_all_biblios_iterator</li>
misc/release_notes/release_notes_22_05_00.md:- [[29625]](http://bugs.koha-community.org/bugzilla3/show_bug.cgi?id=29625) Wrong var name in Koha::BiblioUtils get_all_biblios_iterator
misc/search_tools/rebuild_elasticsearch.pl:use Koha::BiblioUtils;
misc/search_tools/rebuild_elasticsearch.pl:            return ($r, Koha::BiblioUtils->get_from_biblionumber($r, item_data => 1 ));
misc/search_tools/rebuild_elasticsearch.pl:        my $records = Koha::BiblioUtils->get_all_biblios_iterator(%iterator_options);