The Supreme Court decision of “money equals free speech” predates Citizens United by more than four decades (i.e., the 1976 Buckley v. Valeo decision) and “corporate constitutional rights” (i.e., the 1886 Santa Clara v. Southern Pacific Railroad decision) by more than a century.
There was no democratic paradise before Citizens United. Corporations and the super-rich had much greater political power than the average person prior to 2010. Think of the failed efforts to hold banking corporations accountable for making risky loans and misrepresenting the quality of loans that led to the 2007-09 Great Recession, the ongoing decades-long failure to convert to renewable energy sources to ensure a livable world in the face of political pressure from fossil fuel corporations, and the never-ending quest to counter the power of insurance corporations opposed to creating an affordable, comprehensive and universal health care system.