Are these pages totally unique and have their own well sculptured content for example good, engaging, unique category descriptions above and below the product listings ?
Or are they categories which have a list of products, with a unique title and meta description but nothing else unique other than different products ?
Also what else are you alllowing to be indexed ? Tags, filters, paginated pages ? Or are you simply allowing categories and products ?
I assume what your allowing to be indexed is also represented in your sitemap ?
We don't have textual content on the product category pages. We have breadcrumbs (including structured data),then for each product we have the product images (with unique filenames and alt text),product name, and price (all complete with structured data). Apart from a couple of unisex products that appear on both men's and women's pages, the products are unique, though of course many words are common across men's and women's (for example "necklace" or "silver" when it's a category page for women's necklaces or men's necklaces),and I can't see any way around that. We have unique page titles and meta descriptions for each category page.
We don't make use of tags as it's not overly relevant for us given our relatively small number of products; categorisation is sufficient from a user experience perspective. For the same reason we don't have layered navigation. We do have some product categories that run to multiple pages and it's paginated such that Google can follow (ie; no infinite scroll or anything tricky).
Our sitemap includes each of the product category pages and each page has it's canonical set to itself.
I'm at a loss as to what to do here. We could stop selling men's jewellery so that the women's pages get indexed, but why should we have our business dictated to in that way by Google? And what's to stop Google then deciding that women's earrings and women's rings are the same thing? Clearly something about how Google Search works is broken.
Is there any way that I can get Google to thoroughly re-index our site and possibly correct what might have been a bug in existence at the time it was indexed and these canonicals defined?