This question has been brewing in me for a while. One thing that jumps to mind is that technology would be half as advanced as it is now if even that much. "Traditional" wars would still be a thing assuming big bombs didn't get invented. Video games and the internet as concepts wouldn't exist. If mankind did reach the moon by now, it would've been significantly later. All the current leftist bullshit would be gone as there would be no Boomer generation to kickstart it. Religion would likely still have a strong standing in general society. Lots of other stuff too not off the top of my head.