I didn’t sense any hostility in OP’s reply. It sounds like they’re referring to the test, stating its own directions. They’re not making any claims about it, or expressing a lack of understanding, let alone putting words in anyone’s mouth?

You’re right, witnesses to our childhood are important for adult diagnoses. The issue OP’s referring to isn’t whether or not others’ perceptions should be part of the picture, but rather that the wording of many autism tests (such as the one in the post) ask a question that depends on you recalling what others have perceived about you. The test I took didn’t use “say,” instead some questions expected me to somehow know what others think about me. These sorts of questions are kind of twisted to ask an autistic person, since it requires a recursive practice of the social skills we famously struggle with.

Bringing in people from childhood would be far more sensible. However, many of those seeking a diagnosis aren’t going to be brought down that route, as the first thing we’re given is this type of questionnaire. After that, the psych interviews us. I can’t speak for all, but for me that’s all I was given.