The Sherman Antitrust Act makes it illegal to monopolize interstate trade. A monopoly exists when one firm controls the market for a product or service by suppressing competition with anti competitive conduct.
There is no part of the cancel culture, censorship and removal of websites that disagree with your political or cultural point of view that does not violate this act. When you are taking down opposing views in order to eliminate the competition be it political or something like another news or media company, you are violating this act. The exchange of ideas is a service. It is interstate commerce. It does affect businesses and website owners who are targeted.
Why are conservatives not filing massive lawsuits using this act to end the censorship of opposing views and sites for political and financial gain? Repealing 203 will add to censorship. Using this act will break up the monopolies. Our country was founded on freedom of speech and the ability to have opposing viewpoints. This encourages open dialogue and democracy. It provides growth for country as well as culture. Diversity has always been what has made our country stronger. Censorship results in communism, stagnation, and hate.
I believe in a fair market and free exchange of ideas and opinions. We have neither in the US when considering the internet.