I don’t think this is a fair assessment. Sure, there’s problematic Science Fiction that furthers male stereo types. But the problem isn’t genre specific. It’s a problem in all of entertainment. I’d go so far as to say the problem is bigger in the action/adventure genre than it is in Science-Fiction.
Science-Fiction has brought us a lot of macho males. But it has also brought us Sigourney Weaver as Ellen Ripley, the heroine in Alien(s).
Or Linda Hamilton as Sarah Corner in Terminator 2
Are they macho? Kinda depends on your idea of macho. Mostly they are fighters, Ripley against a parasitic Alien race and Corner against homicidal robots. One thing they are not, is sexualized. Or invited into the boys locker room. They pretty much run the show.
How will Whittaker do as the Doctor? I don’t know. We’ll see next year. But what she won’t be doing, is “stepping into a male role”. You’re not a Whovian, so you wouldn’t understand that the role of the Doctor is both defined and incredibly fluid by design. Which includes gender fluid and race fluid. The two other Time Lords in the series already went from male to female (the Master) and from white to black to white (River Song). The potential for the Doctor to take on any human form has always been there. Almost like a promise.
As for your last questions, you probably already know I think you got it backwards.
Storytelling Will Save The World
I know I’ve said this before. It can do with some repeating. Our behavior is dictated in large part by the stories we…
Change comes in entertainment first. And that will allow new generations to make the change in society. The stories we tell are important to imagine what can be. But you know, you don’t have to take my word for it, because who am I, right? So here is Nichelle Nichols recalling how Dr. King pretty much told her the same thing