I would like to create a Collection for Categories, but I don’t want Automatic Pages created for this particular Collection. How can I have a “Collection List” without having Automatic Pages created for each collection item?
Crawlers follow links. No links, nothing to crawl.
If you are using the sitemap feature then you would need to make it custom (removing all items related) and exclude the path to the collection in robots.txt.
Truth is if the collection template has no layout then it has zero content and won’t be indexed even it was found by a search engine bot.