Not so much. Even in the 1800s, it was unusual for girls to get married before they were 18 or so, and the average age for a first marriage was more like 23.
The '14yo child getting married in the 1800s' is the kind of thing that certain conservatives--esp. religious conservatives--like to claim in order to normalize creepy behavior. It happened then--and still happens now in some states!--but even at the time it was very abnormal.
my first partner was a few months older than me, and I always said I was gonna report them for abusing a minor (they were 18 and I was 17) and child grooming.
I'm not American. However, my ex wife was 6 years older than me, and my now and forever wife is 5 years younger than me.
I don't know if that means anything, but, that 11 year age difference between them is real. They are literally from different generations in terms of their mentality, expectations, goals, etc.
I imagine a lot of this could be explained by population growth, and physical and social mobility. There are flat out more people around so it's easier to find a partner you don't hate. There are also more people who are socially acceptable and accessible.