This is too restrictive. The article claims 3 facts are the proof that the genre is ill: (1) 12% of US readers read sci-fi in the last year, (2) current sci-fi

This is too restrictive. The article claims 3 facts are the proof that the genre is ill: (1) 12% of US readers read sci-fi in the last year, (2) current sci-fi best sellers are old books or not really sci-fi, and (3) in the 80s, SF novels were sometimes best sellers. I agree with you that the first fact is a dubious proof. Unfortunately, the others aren't better. The 2013 list of sf best-sellers (the oldest list in the wayback machine from the same source as the article) also contained old books. For instance "Dune" is a best-seller both in 2013 and 2023. And some books were heroic fantasy, not SF, e.g. "Sword Art Online". For the last claim, I could only find 4 SF novels that match the article's claim, out of the 100 of the decade. 3 were related to movies, and 1 to a TV star (Carl Sagan). In the 2010s, there were one novel related to a movie and another SF book. Hardly conclusive. A striking tendency in the recent years is that many of the best-sellers are children books. Young adult novels are also more present. I suspect that, since fewer people read novels, books are very often a gift, something one does not read but buys for others. And for children and teenagers, there's obviously the innuendo that reading books is good for their education.