The full report is in English, and is quite detailed and technical about their methodology and findings. They're not all BAD of course, application crashes, device issues, and security issue reports are how issues get fixed, but there's a lot of unnecessary data being collected and sent to Microsoft, it's been widely known ever since Microsoft advertised (proudly) how many pictures and videos had been viewed on Windows 10.
https://www.bsi.bund.de/SharedDocs/Downloads/DE/BSI/Cyber-Sicherheit/SiSyPHus/Workpackage4_Telemetry...