A post from Pizza Cake Comic
I have never seen anyone react with anything other than general passing interest towards a butterfly
Thats the root of the joke. Its commenting on the fact that the younger generation does not go outside much. Though previous generations have done our damndest to make going outside as terrible as can be imagined
I don’t see any generational clues in the comic. Nor is going outside “terrible”. The presence of the butterfly suggests the environment in this area is “normal” and the indoor kids are the oddity.