Then he would have freaked out over smart phones. I've first hand seen what happens to e.g. sense of direction once use of the navigator-assist becomes habitual. Some auxiliary mental muscle atrophies in the brain.
A navigator of some sort means that I can make up for this shortcoming and that I can explore. It isn't perfect, but much better than my brain does on its own.
However, I still have to use mnemonics to remember which side is port vs starboard (my mnemonic for this is that when facing the bow, aka forwards, port is on the left, because they both have four letters). I imagine this is what you experience when you say you have to think about right vs left, is that pretty close?
Fun little anecdote, my cousin had “right” and “left” tattooed on their wrists because they will forget otherwise. At first I found that unbelievable, but I’ve come to realize how different people can be over the years.
If I pay attention, I can feel my heartbeat. I know that is my left side.
https://commons.m.wikimedia.org/wiki/File:Map_ancient_athens...
Also, Athens (Piraeus) was a major port and therefore had to have a nontrivial share of strangers roaming the streets.