Warning wave 5: Members must be fully assigned, use of unassigned variable: Not replicable in C# 9.0

[RajaniCode]

The documentation states, "Warning wave 5 diagnostics were added in C# 9." However, the given code snippet cannot be replicated for Warning wave 5, Members must be fully assigned, use of unassigned variable, in C# 9.0 as it generates errors CS8773 and CS8773 commented in the following code snippet.
NB:
Visual Studio 2022 Community Edition for Apple Silicon, MacBook Pro M1 Pro, macOS Ventura Version 13.5.2 (22G91).

Code Snippet

public struct Struct
{
    //  Error CS8773: Feature 'struct field initializers' is not available in C# 9.0. Please use language version 10.0 or greater.
    private string data = String.Empty;

    // Error CS8773: Feature 'parameterless struct constructors' is not available in C# 9.0. Please use language version 10.0 or greater.
    public Struct() { }
}

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Document Details

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• ID: fe4ec697-f3a5-3df8-8e43-e49df4f3303b
• Version Independent ID: ee47f321-8c41-a867-c25e-4020b7aa75eb
• Content: C# Compiler warning waves - C#
• Content Source: docs/csharp/language-reference/compiler-messages/warning-waves.md
• Service: dotnet-csharp
• Sub-service: errors-warnings
• GitHub Login: @BillWagner
• Microsoft Alias: wiwagn