It is a weird caveat in that study that sort of makes it a tautology: “We found that at least in men with no known fertility challenges, sperm counts are large

It is a weird caveat in that study that sort of makes it a tautology: “We found that at least in men with no known fertility challenges, sperm counts are largely stable and haven't changed significantly in the last few years, which is reassuring news." It is a weird exclusion. I response I would ask then if the number of males with fertility issues, and thus excluded, are increasing or also stable. They answer that at the end: "“We didn't track men who were fertile who became infertile. I think based upon the literature so far, that might be the case due to obesity or environmental exposures, and more research is needed to definitively answer that question."