But is stil not railroading, unless certain elements are present. All games have a design that forces certain choices to be made. Railroading is not simply that, nor is it simply complaining. Railroading is using GM power to prevent players from wriggling out of a specific conclusion. Railroading is not simply setting up an encounter and forcing players do deal with it. Railroading is when the ordinary state of action-reaction is dispensed with and all choices lead to the same results. Your example is bad, because not dealing with the situation leads to death, which is a different result from living.
It should be possible, however unlikely, to circumvent obstacles in an adventure. With railroading, you stack the deck, and it is irrelevant whether you do this in-game (irresistible force) or out of system (infinite resources arrayed against the player's undesired choices). Simply because a 1st level dwarf fighter cannot slay Orcus is not railroading; the choice is afforded him, but the dwarf probably lacks the ability. If Orcus shows up and insists the dwarf spends the night at a spooky inn or he'll kill him, and the story is the inn, not about Orcus, tht's railroading.