If you think about it, every human is similar in some way to every other. Our lives have differences, and maybe even be unrelatable in extreme circumstances, but I like to think that everyone has the same goal in life. When we share a common problem, we often react in the same way, simply because we all share a common human experience. Rather than having a share subconscious, I think it’s more like every human has almost identical hardware to work with, and the programming (what changes how we live our lives, like your personality) is forced to run along common subroutines but has a lot of room for variance. Sorry if my logic is a bit convoluted, I’m in a hurry =)