My natural impulse is to agree as my orderly mind likes the structure and the belief that only through proper planning can I construct the genius edifice that is my next adventure (joking), but I played with DMs that were master storytellers with minds for detail and creativity that put my overconfident self to shame. Some, select, few, great DMs can run a game on the fly that will blow your mind. The main advantage is that without the prior constraints of a planned structure they can weave the game more tightly around the characters and player choices which can, in turn, make the game more impactful to the players. It isn't for every type of player, and it isn't something I'd expect out of most DMs - but if you're the right type of player and get the opportunity to experience this type of magical game ... cheers.
I'm letting myself get dragged back in for one more thought here:
One perspective does not mean there are not other perspectives. If you read through the post here from 2007 as opposed to yours from 2012, you'll see there are other perspectives. A label has only the meaning we give it ... and we should always be cautious about putting evil into a label when the intent behind it was not. Yes, you can try to draw comparisons to truly offensive labels ... but those arose from a bad place while this one did not. It originally was just something to juxtapose against sandbox and there was rampant discussion of the railroad nature of adventures, especially the Dark Sun ones, when they were released ... I'm betting that a linguist studying the negative perceptions of the term could track it back to those early internet discussions...
I will also say that when you run a game, constraining player options can be a tool within the storytelling. The reason railroading can be frustrating (when done in the derogatory way that some define it) can be a tool that creates tension that can be manipulated and released to move a story. I use it in my "introductory" homebrew campaign that I run for new groups of players. In the setting, the PCs are in a community, something bad happens, and the entire community flees across the seas to a new land. The first four levels of adventuring take place before and during that escape. While there are technically options, there is a clear path that all 7 groups I've run through the start of the campaign have taken. A choice nobody takes is not really a choice, right? The players follow substantially similar versions of the same path until the escape is complete - and we find them in a new land they know nothing about, with a huge number of refugees, and with no real leadership or plan. Going from the frantic escape with a set course to an open field of possibilities and so many nebulous needs without clear direction on how to pursue them has been jarring and uncomfortable every single time - and the resolution of that discomfort sets the course for the next 12 levels of adventuring.