It was also a small town in Japan, small towns tend to not develop much. That said, it could also have been a translation error and he could have been meaning he's from that era.
Since we know he knows what a cellphone is but not a smartphone. Yet, somehow he knows what 4k is(I'm assuming...
The grandparents are in their 40's, the parents look to be in their 20's, and the oldest kid is...how old again? I feel like the math ain't mathing or it is mathing and they get down to business young.
I'm really glad this one didn't follow a romantic path! 80% of the stories here puts the "villainess" with a guy who saves her. And 19% of the others has her get with one of the side characters. I'm glad this one was a story where she really did achieve happiness on her own.
There's a difference between being taught how to take care of yourself and doing that kind of stuff under supervision and straight up thrown into the woods to survive off the land by yourself.
Your grandfather is a big wig in the boy scouts...so he threw you outside and expected you to take care of yourself? Isn't the boy scouts all about teamwork?