Null check on class members not considered for NNBD

main.dart

void main() {
  Example example = Example();
  String? prop;
  final list = [
    if (example.prop != null)
      // Guaranteed to be not-null, but I still have to force it to be not null
      // Only this would work:
      // generateString(example.prop!),
      // This does not work:
      generateString(example.prop),
    // However this does work:
    if (prop != null)
      generateString(prop),
  ];
  print(list);
}

class Example {
  String? prop;
}

String generateString(String prop) {
  return 'prop: $prop';
}