This seems to be a completely modern 4 year old girl.  That is my iPhone she is using, better than me, some of the time.  That is her helmet for bike riding, which she totally is comfortable wearing.   Wow.  When I was 6 or 7 my mother would not let me have a bike.  Looking back, and knowing more today than I did then, I think it might have been due to lack of finances, rather than her reason, stated to me, of "too dangerous".  It was dangerous back then.  No helmet, and bikes were pretty much full size or no bike.

It is an interesting thought experiment.   Have the important things changed all that much?  The kids are curious, kind, laugh a lot, want all sorts of stuff they can not have, like candy, and don't want to have quiet times, or go to bed.  That all seems very much the same as it was 60 years ago.