I think the end goal is for Black and autistic people to be thought of as people first and foremost, and their differences would take a back seat. This is the only way we can be one big happy family. Wouldn't the best way to accomplish this be for the rest to realize that they actually have something in common with the marginalized groups?
Imagine a white supremacist who learns they had a Black ancestor. That would transform their whole world view.
Same with autism: neurotypical people being able to relate to quirks that cause social exclusion isn't something to shut down. We should be celebrating the normalization of these things because that is how they stop being markers of the "other".
Sometimes I wonder what the people who are up in arms about being "not properly" Black, autistic, etc. have as their end game. Perpetual exclusion of the marginalized groups for sympathy points? I think many would gladly trade those points for greater inclusion.