I think some people are just wired to think that way and, as we get older, some people switch to thinking that way. As I get older, I get more concerned that whether or not I mentally decline in one way or the other is just random chance and genetics.
The study refutes that statement. I'm not saying we're invincible, I'm just saying we're less susceptible.
Anyways, afa mental decline with age goes, some of it is random, some of it is genetics, some of it is lifestyle that is 100% in your control.
The more you read about the world, the better things stick in your head, the more connections you make, and the more you know. If you leave the critical thinking to some internet celebrity with no incentive to be credible, you end up being coddled from a lot of the news and get basic facts wrong.