It seems arbitrary to set the limit of how much pointless busywork we need as just the amount you're used to. Maybe maps are already dumbing it down too much and we should work out directions from a textual description of landmarks and compass bearings that's not specific to our route? In my opinion, dependency on turn-by-turn directions is fine because we do actually have the machines to do it for us. We're equally dependent on all sorts of useful things that free us to think about something actually useful that really can't be done for us. For example, consumer law means we can walk into a shop and buy something without negotiating a contract with each seller and working out all the ways we might get cheated.

Maybe the place to draw the line is different for each individual and depends on if they're really spending their freed-up time doing something useful or wasting it doing something unproductive and self-destructive.