SerializeReferenceDropdown Versions Save

public class TestShapesForSRD : MonoBehaviour
{
    [SerializeReference, SerializeReferenceDropdown]
    private ISimpleGenericData<int> _intData;
}

public interface ISimpleGenericData<TData> : IAbstractData
{
    public TData Data { get; }
}

[Serializable]
public class GenericData<TData> : ISimpleGenericData<TData>
{
    [SerializeField] private TData _data;

    public TData Data => _data;
}

[Serializable]
public class GenericKeyValuePair<TKeyData, TValueData> : ISimpleGenericData<TKeyData>, IAbstractData
{
    [SerializeField] private TKeyData _key;
    [SerializeField] private TValueData _value;
    public TKeyData Data => _key;
}