Ensure that only published products (i.e. assigned to at least 1 product category) may be ordered
See Optimizely Ticket #1713060
Problem: only a product with a deactivation date will ensure end-customer cannot add it to their cart via re-order functionality or saved lists. Our business have multiple websites (1 per country) and often a product that active in more than 1 country ends up being removed from country A, yet still published in country B.
Solution: have the product category assignment the source of truth. If a product is not published in at least 1 product category in site A, then it cannot be ordered or re-ordered in site A.

Thank you for submitting this request! We have added this item to our backlog for future consideration and prioritization.
If we were to change this behavior in the future we would be sure to approach in as much of a non-breaking way as possible to prevent issues from customers who currently choose to take orders for non-categorized products.