OP stated:

For pretty much the entireity of our existence, we didn’t have borders. […]

Please point me towards a part of our existance where we didn’t have any types of borders. I deliberatly went all the way back to our beginnings as a species to point out that even then borders existed in some form.

As for the “shift and flow” part, I clearly stated:

[…] We just evolved the means to make them somewhat permanent. […]

So, what exaclty is there pseudo-intellectual in my statement?