Sidewalk curb cuts benefit people in wheelchairs but also help everyone else. Is this also true when making buttons bigger, fonts larger, contrast stronger, timeouts longer, etc.? Or do younger people have a harder time using web sites and apps?
Not at all. There are many studies demonstrating that general adjustments for older people are of benefit for both the elder and the younger extremes. These studies also demonstrate younger demographics (specially teenagers and kids) prefer big, bold, contrasting elements over subtle, low contrast elements.
While there are many misconceptions around this issue, research shows those are just that: misconceptions. Just in case you want to know more, here you have an interesting article on these myths (because they're just that: myths). You could also take a look to this document with research and even some formulas
So, in short, to answer your question: no, there's no relation
I always ask people:
Have you ever thought about an application: 'This is to easy to work with, I can't work like this!'
They always answer no, sometimes they ask something about missing functions. But an application that is missing some parts is not the same as an easy one.
If there is any difference it might be more in the marketing department: What attracts young people to return to a webshop and buy, might totally be different to what older people want to see. But even then, there's no reason why you can't cater to both groups. And don't forget the accessibility, sometimes you don't need to implement the functions people need but only make sure their own browser or computer add-ons can use your creations effectively. (Think about screenreaders for example)
We're all still human, we do have a lot in common because of being the same species.