If you write about an autistic child, I have every right to judge your words. Because I have a child with autism and my journey with that child is authentic, and everyone with an authentic story like mine has the same journey.
Everyone's journey is different. Matthew loves stuffed cats, but what if another author has their character liking stuffed dogs. Could I berate them for getting things ‘wrong'? Of course not. Now if they wrote that all people on the spectrum are like Rain Man, then I could argue, hang on, what about my son? He's nothing like that. How can you make sweeping statements like that about a whole spectrum of people? I wouldn't though, I would just walk on by and not read that story. Simple.
As authors, whatever gender or identity, I genuinely think we have a responsibility to respect differences and understand everyone's life journey is different. We also have to accept that sometimes we get things wrong when we don't fully understand this.
I found an article a while back in which other authors much more eloquent than me spoke up about cultural appropriation.
I picked the following from the article and hope I live by these maxims in my writing:
“We can write who we are not and do it well if we write with passion, strength – and care. We’re bound to get it wrong sometimes, but that doesn’t mean we shouldn’t try. If we want our writing to reflect the truth, then our characters and their experiences must be as diverse as the world in which we live.” Stella Duffy
“… you have to try to do it well. You have to be familiar with whatever tropes might apply to your character: racist, sexist, homophobic, sizeist, ableist, antisemitic and anything else. It’s not OK, for example, to make your Chinese character shifty and inscrutable or your fat character stupid and lazy: you need to have learned enough to understand where these false ideas come from and why it’s so pernicious to replicate them. Do better. Treat your characters as human beings. Write them as people not ideas or stereotypes.” Naomi Alderman
All I can say is, I write the truth of my characters, and I hope never to cause true offense.