Male fertility on the decline?

This article is extraordinarily dumb and bad. It opens with several paragraphs of useless irrelevant padding, and then:

"We are producing half the sperm our grandfathers did. We are half as fertile.

"[A] meta-analysis by a team of epidemiologists, clinicians, and researchers... culled data from 185 studies, which examined semen from almost 43,000 men. It showed that the human race is apparently on a trend line toward becoming unable to reproduce itself...

"That path, in its darkest reaches, leads to no more naturally conceived babies and potentially to no babies at all—and the final generation of Homo sapiens will roam the earth knowing they will be the last of their kind."

The first two quoted sentences are wrong, because marginal utility is still a thing, and because actual fertility rates haven't fallen. On the contrary, modern medicine makes it much easier to conceive a child if you want to, and the loss to sperm count has been mostly a loss from an enormous built-in safety factor. It's something to worry about, yes, but "We are half as fertile" is just false.

To reach its nightmare scenario the article assumes many things that are not in evidence:

Is it really the case that the trend will continue forever?

Is it really the case that we will never find the cause of this development?

If our grandparents were not suffering from it, is it really so implausible that we might get back to the conditions they enjoyed? (Don't say "pollution," because if anything we live in a much less polluted environment nowadays, aside from greenhouse gases, which aren't likely to be the problem.)

And, as a last resort: Is it really the case that in all of the human gene pool, there are NO men who are comparatively resistant to the trend, and who can pass that trait along?