When you are young, your relationships are not at all complicated. And why should they be? You have no real experiences with a long term relationship, so , you don’t really know what to expect.
But, as you get older, you are wiser and much more experienced. So, relationships become much more complicated. And because of that, on-line dating is much more difficult. After all, you don’t want to repeat the mistakes of the past.
When you were young, you could naively enter into a relationship. But not so now that you are older. Therefore, you “pass” on a lot of potential mates just because you can see them for what they really are.
So, when you see these ads for couples that found each other on-line, just remember that they probably lack the experiences to make sound decisions on a mate.