It’s a lot harder to notice the additional incoherence due to aging on people who constantly say things uncorrelated with objective truth (what’s - and I kid you not - scientifically called “bullshitting”) - when they’re young they’ll say whatever independently of truthfulness because they’re trying to manipulate others, whilst when they’re older they’ll say whatever independently of truthfulness because they’re mentally lost - the output is similar but the reason is different, so it’s harder to tell from the outside how much is their bullshit the product of an aged mind.