This only show that the protection doesn't work like it needs.When I run avast!'s Ransomware Shield, only app that even raised Ransomware Shield alert was for FileOptimizer. It's a relatively unknown app designed to trim down files to smallest possible size without decreasing quality. Fair enough. But everything else works seamlessly without any alerts. Paint.NET, MusicBee, CrystalDiskInfo etc. No issues while protecting exact same folders.
Controlled folder access helps you protect valuable data from malicious apps and threats, such as ransomware. It protects your data by checking against a list of known, trusted apps. Controlled folder access is supported on Windows Server 2019 as well as Windows 10 clients. It can be turned on via the Windows Security App, or from the Microsoft Endpoint Configuration Manager and Intune, for managed devices. Controlled folder access works best with Microsoft Defender Advanced Threat Protection, which gives you detailed reporting into controlled folder access events and blocks as part of the usual alert investigation scenarios.
Controlled folder access works by only allowing apps to access protected folders if the app is included on a list of trusted software. If an app isn't on the list, Controlled folder access will block it from making changes to files inside protected folders.