That's true. I have read several of her nonfiction books, and they do contain genuine arguments with a logical structure relating conclusions and premises. Some of them are pretty good. I like the Romantic Manifesto, and a couple of the essays in Philosophy:who needs it. The title essay is perceptive, and Selfishness without a Self is brilliant and original. However, some of the other essays are terrible beyond belief, especially Kant and Sullivan. It would be overly charitable to say she misreads Kant. It's clear she hasn't ever read him at all. This essay was my first attempt to separate the wheat from the chaff in Rand.

https://www.academia.edu/752850/Altruism_Pity_and_Compassion_Significant_and_Ignored_Differences

This lecture was much later, and places her in the context of other Libertarian Thinkers.

https://www.academia.edu/5393180/A_Critique_of_Libertarianism