The current PS default-bootstrap breadcrumb.tpl doesn’t follow current guidance for breadcrumb schema from schema.org. It uses data-vocabulary.org.
I propose switching to schema.org and using itemlist just as defined at google developers. See https://developers.google.com/search/docs/data-types/breadcrumbs example two in microdata.
Google Structured Data Testing Tool can render some pages to show you what one will see in rich snippets. A product page is ignoring breadcrumbs currently and this should get that into the product rich snippet.