Since the publication of the theory, three entrenched factions have appeared in the autism causation world. A first faction believes autism can never be a problem, so cannot need curing or be a disability. A second faction believes that vaccines, either MMR or mercury-containing thimerosal (or latestly Hep-B) have caused autism to increase. A third faction is the corporate medical establishment which promotes the idea that autism is a primarily genetic disorder and that the increase is not real but just the effect of increased awareness or diagnosis.
My involvement in autism research pre-dates all these factions and I partly disagree with all of them, but also partly agree with them all. I see some sound work from all of them and also some abysmally unsound work from all of them. I'm not in the business of taking sides. I judge publications on their reasoning and evidence rather than the partisanship of the conclusions or authors. In my experience as an author of theories, I have to conclude that it is very rare for even biased parties to actually falsify their raw data; if they did so it would be impossible for my theories to so comfortably accommodate them as they do.
Meanwhile, I do see from all sides wildly perverse interpretations (or misrepresentations?) of what that data tells us, and displays of stupendous incompetence (or disingenuousness?) from all sides. But I leave to others to speculate what if any motives or secret conspiracies may lie behind these discrepancies. In my view it usually (outside of therapeutic trials for instance) remains the case that scientific questions are best answered by reference to just the published (and "unpublished") scientific evidence, with only the most occasional "pinch of salt".