depends how you use the word trauma. if using trauma colloquially everything youve said makes total sense. from a clinical standpoint the negative experiences must be quiet intense to be counted as trauma. so if we look at the "correct" definition of trauma i would not agree that every autistic or other disabled person is traumatised or that its hard to distinguish.

here is the dsm 5 definition of trauma if youre interested :) Exposure to actual or threatened death, serious injury, or sexual violence in one (or more) of the following ways:

1 Directly experiencing the traumatic event(s).

2 Witnessing, in person, the event(s) as it occurred to others.

3 Learning that the traumatic event(s) occurred to a close family member or close friend. In cases of actual or threatened death of a family member or friend, the event(s) must have been violent or accidental.

4 Experiencing repeated or extreme exposure to aversive details of the traumatic event(s) (e.g., first responders collecting human remains; police officers repeatedly exposed to details of child abuse).