The term itself is used to complain about feeling railroaded places you didn't want to go, which took up your time while you were there, and ultimately you wished you could get away from but couldn't because you always would have to get back on the train. The term is not meant for the mere fact you can be taken somewhere by the train. If it's where you're going, and efficient, it's a great format.
Players can feel led by the nose in encounters, in dungeons or other locations, or in the story. You can write any of these without leading them by the nose, though. The DM establishes the relative importance of everything, including the characters in terms of how they fit into the setting and what their opportunities will be even if they always get what they want.
A good railroad is a series of events and challenges, maintaining relevance or spicing things up, where the players can get off at any time and still be able to play with the same time. I am trying to think of a better term, given the negative connotations of railroad. Perhaps it would be a story, or an adventure synopsis. The players can decide what this will be, or the DM can make events happen.