The parent explicitly acknowledged that there do exist good sci-fi writers, so I don't know that your list contradicts anything.
I think it goes back to Sturgeon's Law. There's still plenty of bad sci-fi. Amongst the bad sci-fi, I think the above remains a common failing, along with myriad other failings. I'm not sure whether it is a more common failing in SF than in other genres - I try not to read enough bad books of any type to have a representative sample. I'd believe that it is, because author attention gets directed to other "more interesting" things. But I'd also believe that is not, and the perception is simply confirmation bias.
I think it goes back to Sturgeon's Law. There's still plenty of bad sci-fi. Amongst the bad sci-fi, I think the above remains a common failing, along with myriad other failings. I'm not sure whether it is a more common failing in SF than in other genres - I try not to read enough bad books of any type to have a representative sample. I'd believe that it is, because author attention gets directed to other "more interesting" things. But I'd also believe that is not, and the perception is simply confirmation bias.