Presumably if the players are choosing a direction it's because they want to go to a certain specific place that they do know about.
I don't think so. Not to say that I'm hard disagreeing with you, just that I think it's really worthwhile to open up our perspective about what decision-making matters in a RPG.
In my Prince Valiant game the PCs wanted to go from Britain to Constantinople. So we Google up a map of Europe, and talk about how they are going to do that. Given there's a map, they have to nominate some or other route. It doesn't follow that anything is expected to turn on this.
I think we have to be very careful about assuming, because D&D's history begins with maze exploration (where obviously going left or right
should matter), that decisions about which way to go
always matter. And conversely, just because D&D's history has had creatures that always attack (eg some undead, or hobgoblins vs elves) or that need special attacks to damage them (eg many oozes) and that's fair enough because it's part of the puzzle-solving aspect of play, I think we can't just assume that it's
never railroading to include an encounter that has only one way in or one way out.
Turning to a different sort of example, but still trying to bring assumptions to the surface and recognise the diversity of RPG play: I mostly play RPGs where it's taken for granted that an effect of action resolution might be that the GM gets to tell a player how his/her PC feels (D&D 4e has various fear effects; Burning Wheel has Steel and Duels of Wits; Classic Traveller has player-facing morale; MHRP/Cortex+ Heroic has mental and emotional stress; etc). Conversely, a lot of D&D 5e players seem to object to that very strongly. The objectors have identified one particular aspect of player decision-making - the
characterisation of the PC - as an object of meaningful choice. Fair enough! But in the games I prefer characterisation of the PC isn't where the main action is for players.
Different decisions matter for different players who are looking for different things from their RPGing.