It was closer in time, and younger. It was more just a "when ever they mature and seem old enough" thong rather than a specific age. Which meant some 12 year olds had jobs, some 14 year olds were going off to war, or serving on ships.

Here's an example of how mature some people thought kids were in 1910 or so:

https://en.wikipedia.org/wiki/Louis_Abernathy_and_Temple_Abernathy

A couple hundred hears ago, children were losing life and limb working 12 hour shifts in factories and mines. This is not a great example of how things were superior in "the good old days" - and also a perfect example of why we should be weary when anyone, ourselves included, speak of how the past was a better time.