Which was not a robber baron?

Andrew Carnegie is often identified as a robber baron due to his monopolistic practices in the steel industry, while figures like John D. Rockefeller and Cornelius Vanderbilt are also labeled as such for their aggressive business tactics. However, someone like Thomas Edison, who is recognized more for his innovations and contributions to technology than for exploitative business practices, would not typically be classified as a robber baron. Instead, he is seen as an inventor and entrepreneur who advanced industries through his inventions.