I'm not a scientist. I'm going to let the good folks like Steven Novella handle whether this is a hiccup in data, a sign of over-diagnoses, a wider diagnostic criteria, or simply what it is seen as now: A sign that we've been neglecting some with autism who manifest differently from what's expected.
All I have to say is this: If this is true, then it is critically important, now, more than ever, that we fight for the rights of autistic people in all areas: schooling, healthcare, education, employment, equal participation, and anything else which may have been previously neglected. Because if there is 1 in every 38 people with autism, we are going to need all the support and understanding we can get.
We are here to stay, world of neurotypicals. You can't sweep us under the rug anymore.