Should one be looking for autism symptoms in add kids anyway, since there's no fix for the autism part?

Yes. Though there is no cure for autism, recognition can lead to appropriate treatment planning, behavioral management and the recruitment of resources that might be helpful in school.
There's no "fix" For autism or adhd. Valid diagnosis + multimodal ( medical, behavioral & environmental) management reduce impairments found in these 2 distinct chronic neurodevelopmental disorders. The aap recommends universal screening of 18-mo.& 2-yr-olds for autism. 40-70% of kids with autism have adhd, but adhd doesn't predispose a child to have autism. If concerned, seek psychological & psychiatric evals.
Yes, look. Although there is no "cure" for autism, effective and beneficial treatments exist. What's more, we know that the earlier these treatment interventions are started, the better the child's prognosis. Consequently, one should definitely look for co-morbid autism.