It was meant as a joke, but it came out a little unnerved. What did he mean the actual past, because Robin could go with the flow. She really could, but maybe not a waterfall, you know? More like a trickle of weird things happening would be nice. It just seemed like Hawkins was more of the "if it rains, it pours" variety of weird, and only if you were in the know. Otherwise, it was a bunch of parents and kids going on like there wasn't a whole other dimension under theirs where monsters and evil things lurked.