Anti-cyborg and anti-android bigotry have been a theme in science fiction since forever, both as parallels for real world bigotry and an expectation of what will almost definitely happen in the future if such living beings came to exist. Nobody should have been surprised that it was explored in this one thing (which I admit I know nothing about) let alone it happening for real. I'm willing to bet everyone who complained about it doesn't consume much in the way of fiction at all and is rather ignorant about anything that doesn't happen online.