I've not heard that about Neanderthals before, but then I've not read much about prehistory. They obviously had some differences to us and the could well have been smarter. Life was very different back then when just surviving was hard and taking time to work on art was a big investment. Just the fact that they did it in deep caves with crappy lights is impressive. Humans went on to do some impressive stuff like all these megaliths etc scattered around Europe. Those needed people to be organised when there was no writing (that we know of) and no money. Then that knowledge got lost for centuries. I don't think people have got much smarter, but we have more resources now and then some of us get lazy and act stupid as we can survive anyway.

Stay curious.

BTW I've been reading various graphic novels. I tend to stay away from mainstream superhero stuff and have enjoyed Sandman, Snowpiercer, Umbrella Academy, some Alan Moore and others, including some from Hive people.