Was John D Rockefeller A Tyrant

Today, we know that John D Rockefeller the founder of Standard Oil company used his power to eliminate his competitors and tried to create a monopoly in oil industry. He made secret rebates with railroad companies, so railroads gave his company a lower rate than his competitors. As a result, he could drive out them from the market. In order to destroy the competitors, he raised prices in the areas with no competition, and lower prices in the areas with competition. His strategies ruined competitors, and made them to sell out or go bankrupt. He was considered a ruthless or tyrant who had a lot of enemies, but it was not considered illegal or unethical to monopolize an industry. I think after his first priority which was making money, he was