It's not facetious. It's quite the stretch to say that if you assume literally any injection could cure any disease, it's OK to describe any found correlation as a "link".

This sort of intellectual looseness is not free. People are learning to treat claims by scientists as untrue, and it's partly because of this sort of press release/paper hacking.

Finding a correlation between two random medical data sets does not mean there is a "link" in any English that normal people would use it. It definitely does not mean there's an "effect" or that one thing "reduces" the other. It might mean there's something worth a followup investigation there, though given the prevalence of non-reproducible p-hacked results in science, also maybe not.

Regardless, before doing press releases and going to the public with such a claim there is a large amount of work needing to be done to actually prove causality. Moreover you'd then want to ask why does such a thing happen when there is no prior reason to suspect such an impact.