We need more roles filled like how they filled Ripley's role in Alien:
Write a unisex role. If a love interest is necessary, make that love interest unisex as well. Fill the role with the best actor for the part (best pairing if a love interest is necessary), and that's it. Don't write a strong female for the purpose of having a strong female, because that character will likely suck.
That's like saying don't write a sci-fi story for the purpose of having a sci-fi story.
If somebody wants to write a strong female (or whatever else) character, why shouldn't they? The only thing that matters is how well you execute that
Perhaps you miss interpreted his phrase.
And it really goes to the same point, you don't write a sci-fi for the sake of being sci-fi, you want to write a great story and being sci-fi is just the theme, canvas, boundary, etc. Same you create a great char and if so happen you put as a female great.
But when you decide to make a sci-fi or strong female for the sake of it you'll fall in the pitfal of not great execution. That is one of the points discussed a lot in this thread that when for diversity sakes some movies or games define a woman they make her flaweless to not get complains from SJW and that ends up being shallow and boring.