I wonder if this supports a cleaner way to throw when the target property's parent object is null? With null-coalescing assignment, you can do the following which will throw when 'x' is null:

  string x = null;
  string y = x ?? throw new ArgumentException("x is null");

  customer?.Name = newName ?? throw new InvalidOperationException("customer is null");

  (customer ?? throw new InvalidOperationException("customer is null")).Name = newName ?? throw new ArgumentException("newName is null");