I've often found, too, that age can be 'pigeonholing' and that preference safely overrules age. Ie, you wouldn't want to say 'this is Sara, she's a 65 year old, and so doesn't use the app'. Rather, 'this is Sara, 65, who, because of security concerns, doesn't like to use the app'. The focus shifts from age (which can be read as a generalisation, and so excludes users who don't fall into that generalisation) to preference (which is age-agnostic, and can be firmly designed for.)
Doesn't affect much, just something I personally like to bear in mind when writing personas. (There can of course be preferences tied to age, but it's important to design for the former not the latter; you cover a broader range of behaviours/preferences.)