Surprisingly, it didn’t. 16-year olds were considered near-adults at the time. They could drive and be legally married in some states. In fact, there were even efforts to allow them to vote. Moreover, if you look at many past photos of 16-year-olds, they actually look older than 16-year olds now.
This wasn’t just something that reflected the loose times of the 60s and 70s. When my great-grandfather married my great-grandmother, he was 27 and she had just turned 16. This was in 1914.