I can believe this but I doubt it is always true especially when you are talking about 5 or 10 years age difference. I just don't see 5 or 10 years a big deal.Even a five-year age difference makes a couple 18 percent more likely to get divorced, compared to a couple born on or around the same year.
For a Lasting Marriage, Try Marrying Someone Your Own Age - The Atlantic
Now when you get into a much larger age difference I doubt you would have that much in common. I would wonder if the younger person is actually attracted to the older one.