All groupings are arbitrary, it just (sometimes) provides utility to group on some shared attributes. It would be more accurate to say boomers trust ai more, not because they're necessarily stupider (though lead poisoning was extremely common through leaded gasoline), but being older does mean you had less access to multiculturalism, less inundation with scams and technology growing up, and more propaganda that is harder to find counterpoints to.
It's fully accurate to say "older people generally are more close-minded and trust AI more" without that being an attack on any particular old person. That's a reality old people and young people need to be aware of, whether it's for an older person to reflect if that's happening to them, or a younger person to help an older person with.