Steam Spy was a third-party service that scanned public accounts through the service and provided playtime and ownership status for some games. These were some of the only sales and performance metrics that were publicly available for these games. However, after tech companies have been more concerned about protecting users' privacy, Valve has adjusted the default privacy settings for users by hiding the games they owned and played by default. Users had to decide that Steam Spy could collect data.
That's probably the reason the Steam Spy was sentenced to death. Developer Sergey Galyonkin reworked the service, but because he switched from a model based on real-time data to machine learning, it was less accurate. Valve already has access to all the data necessary to create its own service, such as Steam Spy. According to PC Games N Ewert concluded, "We're working on new tools and new ways to get data from Steam, and we hope that data can be more accurate and useful than Steam Spy previously offered . "