JsonSerializer should throw if nullable is enabled and non-null values are null during deserialization

[Trolldemorted]

Description

Imagine this program:

class Cat
{
    public string Name { get; set; } = default!;
    public string? Foo { get; set; }
    public override string ToString() { return Name ?? "ERROR"; }
}
class Program
{
    static void Main(string[] args)
    {
        var cat = JsonSerializer.Deserialize<Cat>("{}");
        Console.WriteLine(cat);
    }
}

I expected that the JsonSerializer would throw if the non-nullable values are not present in the json string.

Configuration

<TargetFramework>netcoreapp3.1</TargetFramework>

Regression?

no (?)

Other information

We have not found an easy workaround to conveniently enforce null safety for a huge amount of classes.

[Tornhoof]

Looks like a duplicate of #1256

[Trolldemorted]

Sorry, you are right!