Female/afab people can absolutely have a different set of autistic traits, but also:
I have super stereotypical traits and I still didn't get diagnosed until I was an adult. And even then the only reason I got diagnosed was because a friend straight up told me I was autistic and insisted that I needed resources.
have an absurdly strong interest and affinity for STEM subjects
was at one point fascinated with trains
refused to wear anything other than jersey cotton until I was 10
can't stand loud noises or busy places
had atypical verbal development and used mostly sign language for a couple years
would do weird shit like sit completely still for hours because I was using my imagination
was routinely compared to Sheldon Cooper
And I still wasn't diagnosed until I demanded it.
And, while I understand that the under-diagnosis of afab people is the result of research bias, i.e. Hans Asperger thought he had discovered a condition exclusive to males, and research bias can be propogated through decades and even centuries, I don't think that the research system is solely to blame.
Because here's the thing; there was no shortage of people that should have noticed I was autistic. I had almost 50 teachers from kindergarten through high school. I had several therapists.
And the fact that none of those people noticed, when they specifically studied child development or education or psychology, and at baseline knew how a typically developing child behaved, tells me that the issue of underdiagnosis isn't only the fault of scientific convention.
a. being perceived as female completely excludes you from diagnosis
b. our idea of intellect is so synonymous with autism and knowledge of autism is so limited that the two states are inseparable