SF hasn't had anything innovative and interesting since cyberpunk.
And fantasy hasn't had anything innovative and interesting since Tolkien.
And literary mainstream fiction hasn't had anything innovative and interesting since Faulkner.
I guess the thread should be retitled, "Is Fiction
in a state of exhaustion?"
Again having not read the works cited to support the thesis that SF is exhausted, I can only ask: is part of the problem that SF authors have not adhered to the dictates of the genre, thus creating works that do not live up to the standards of 'classic' science fiction works? If so, that leads to the question of what is required of a good sci-fi story.
Leaving aside the general requirements for good fiction-writing, I suppose it's a truism to say that a good sci-fi story should embody, in some sense, the ethos of science itself. So to distinguish from fantasy, your cool new tech toys should be scientifically plausible, with your scientific extrapolations being plausible as well. Your fictional worlds have to have some basis in scientific reality; so no more Venusian jungles, or more to the point fewer convenient M-class worlds. If the characters of the story are faced with a problem, be it technical, social or political, we would expect them to use the tools of actual or plausible natural and/or social sciences, to deal with these problems.
This doesn't mean that everyone or everything in the story has to revolve around science; clashes between different worldviews having different approaches and acceptances of the scientific method, are always compelling.
My guess is, the declining state of American education notwithstanding, most serious sci-fi authors have at least some familiarity and understanding of multiple fields of science. Maybe new SF works are increasingly reflecting the fact that our culture is showing signs of moving away from accepting science. If so, I just hope the writing community does not water down the essentials of sci-fi in their future works.