Anecdotal evidence: I remember how my 65 years old dad changed from a large-minded, world-traveling retired professor to an avid consumer of fake news in the span of fewer than two years. Yes, it was a shock, but most of all I am mortified that this could happen to me as well when I get to his age.
I remember a boss not so long ago, similar age. Started having a rant about a woman that was emailing him, flirting with him. I realised it was some kind of phishing thing. He just took it at face value. He wasn't naïve, and had all his faculties, so it really stuck out. Maybe its like country bumpkins without street smarts, maybe they just havent learned the defenses needed?
I would like to see a study using the same subjects but check to see if they can tell what is a Google search result and what is an ad.