I find it hard to believe that bad literary technique could elicit a sneer. Stilted dialog might result in, at most, bemused indifference or perhaps sadness at witnessing a failure. I'd bet you don't sneer at flat-earthers because they don't threaten your worldview. A sneer is reserved for much greater transgressions and you are afraid to admit that Rand's works, as art, presents a worldview that clashes with your own.

Which just goes to show that authors with something to say should not be put off if they're 'stylistically challenged'. David Lindsay's Voyage to Arcturus is another glaring example. The dialogue is pathetic but the novel is an amazing tour de force.