When a product is removed from a product feed upload, the product gets marked as 'inactive' in the product catalog feed. It will still be visible in the catalogue but it will not be recommended.
Inactive products will automatically disappear after approximately 180 days.
If a product that was in a previous feed does not appear in a new feed, this product will be marked as inactive. Inactive products get removed from the product catalogue after some time, roughly after 180 days. Inactive products should not be getting served in recommendations.
Screenshot showing inactive product