People seem to have a wildly innacurate view of what sensitivity readers are and what they do. But they also seem to have a bizarre view of the creative process. No idea is perfect from the very beginning and it's rarely perfect throughout the process. Writers send books to editors and alpha readers and beta readers to get other people's impressions of their work, to see if they're getting across what they want to get across the way they want to get it across, sensitivity readers are just another version of that. I even have an excellent example.
Brandon Sanderson in his book Mistborn: The Final Empire wanted to write a well-rounded, interesting female protagonist for the book. He succeeded in doing that. But he didn't realize until after things were too far along that all the other main and supporting characters in that book were guys. He as expressed his regret about that fact and wishes he'd noticed sooner so that he could have changed that. Sensitivity readers might have caught that out and thus led to a book more in keeping with his vision and ideals.
Obviously no one wants a creators creative vision to be stamped out, but sensitivity readers job isn't to overrule, it's to point out where a creator's lack of certain lived experiences are causing them to include details that would make their potential audience feel excluded or hurt. They can also point out to creators where their depictions of people unlike them are falling into unintentional cliches and pitfalls, which can lead to those characters being changed in ways that make them more true to life and interesting. And if a creator *wants* to keep those aspects in their work, then in most cases they can, it's not like there's some sort of wide practice of sensitivity readers being able to just demand a change be made or the book won't be printed.
