The standalone website/official homepage relationship is often misused. As far as I understand it the relationship should only be used for URLs that do not contain a path after the hostname, eg. www.albumtitle.com/. If this is right, a report could be created with URLs using this relationship that do contain a path, suggesting that they be removed.

Note: While URLs of the form www.albumtitle.com/index.php or similar should not be removed, they probably should be shortened according to https://musicbrainz.org/doc/Style/Relationships/URLs

For examples of how the relationship is being used, see https://musicbrainz.org/search/edits?auto_edit_filter=&combinator=and&conditions.0.args=287&conditions.0.field=link_type&conditions.0.operator=%3D&negation=0&order=desc&page=1