`Microsoft.Win32.RegistryKey.DeleteSubKeyTree` deletes subkeys recursively. It can use [RegDeleteTreeW](https://learn.microsoft.com/windows/win32/api/winreg/nf-winreg-regdeletetreew) to save system calls. https://github.com/dotnet/runtime/blob/1abc433c5f18a8e5f889739b983c55903ffc6722/src/libraries/Microsoft.Win32.Registry/src/Microsoft/Win32/RegistryKey.cs#L322