That complaint is reasonable when some headline makes some simple result sound like a possible cure for some dread condition. When it's just complaining about an article that's simply general biological research, it becomes annoying.
Agreed, I regularly make comments about how the latest "eating X shown to improve Y" study is effectively an irrelevant guide for your own behavior when it's "just shown in mice". People think they, as a human, should copy a diet that probably doesn't even work in several mice strains, and has a reasonably high chance of never working in humans. So saying "in mice" is a way of saying "maybe don't change your grocery list just yet", which is sensible.
But there's nothing in this article that purports to guide/influence the behavior of a member of the general public who wants to promote hair growth. It's just research.
