Lanefan
Victoria Rules
This.Now, I know that there are completely different games and types of scenario, I've explored my faire share over the years. But pretending that having any sort of plot is akin to some level of railroading is a bit too much for me to digest.
It only becomes railroading if-when the plot overly interferes to the point where the PCs actions are in effect declared for them. And even then it's not always bad (though it certainly can be!); look at the transition from the 1e modules A3 to A4 for example, where A4 cannot be run unless the party get captured at the end of A3 and so at the end of A3 they're going to get captured pretty much no matter what they do other than fall on their own swords.
That said, back-plot can very much still be overdone or done in a too-heavy-handed way, as per my The Gauntlet experience just above. It's a fine line to walk sometimes, never mind that the perfect line at one table might be a disaster for another.