To be clear, the link is between anticholinergics, of which some first-generation antihistamines are, while others are less potent as anticholinergics.

Best I can tell, the clinical advice is to avoid prescribing these to patients aged 65 and above.

I'd still generally prefer sleeping completely naturally, but I think comments like these might make people avoid medicine that could help them improve their sleep over time. I was massively helped by the use of Hydroxyzine when I was younger, which helped me get on a path to better sleep and overall health.