I propose that, we, as a culture, are actually less intelligent than generations before. Sure, we’ve had technological advances but, have actually become dumber.
This is because of a few things:
1) a lack of physical movement and physical adversity. Being uncomfortable and having to move daily, I propose, helps promote creativity due to new connections between mind, body, and environment. Not to mention, necessity being the mother of invention.
2) Lack of connection with a complex environment. Yes, our cities can be complicated but, generally, they rely on over-stimulation of the senses. Instead, a less human-created environment relies more on skill in use of the senses and subtlety. One is hit by walls of noise, light, smell in cities whereas in more natural environments they are all part of a multitude like birdsong, scent on the wind or colors of different plants.
3) The lack of environment means a disconnect and loss from all of the world knowledge required for survival and nutritional diversity. For example, all the foods that one could forage if we knew what plants were edible outside of a grocery store. Yes, those vegetables are obviously good for us but, what if we had hundreds of options or vegetables to mix together instead of the basic say, 2 dozen that we usually see in stores.
This knowledge of edible foods then includes not only what are safe to eat but, things that look similar and are not safe, remembering locations where those plants can be found, what sort of soil they prefer and who knows how many other important information related to those edible plants.
4) We no longer have a culture of story-telling or music-making. Instead, we watch stories and listen to music, very few people actually create these as parts of the culture or even continue folk-songs and stories. How much more creative would an individual be filled with myths, legends, lore and stories that are carried through being told stories at night? Then mix in all sorts of different songs for different situations that they can start singing right away.
Essentially not having to work for food, worry about not having food or a variety of ways to communicate and share time together, has led us down a path of being able to do a few things particularly well but lacking in a much larger domain which, I think, can be limiting our intellect as a culture.