[Too late, sorry for the delay, but I had to think about it.]

That ooks like a good reason. Looking at https://learn.microsoft.com/en-us/dotnet/csharp/language-ref... , the magic is in the LHS or the RHS, and in ??= the magic is explicitly in the connection. Here, IMHO, the problem is that the magic jumps from one side to the other. Anyway, I don't use C#.