The now-deprecated reporting of Deals_Won used to enable us to see which Products were sold/included with the Deal and it was a crucial report to understand which Products our team is selling.
The new Insights doesn't enable this detail, nor does building a custom filter to report on it. It would be OK in the filtered reporting (personally I prefer to get it there so I can quickly export results to .csv) but within Insights is also important to break out and visualize Products trending.
It is imperative to track Products_Sold (Won) in a sales database.
Please bring it back ASAP.