A business reform was indeed necessary.
The first agreeable sentence is Railroads and big businesses benefited the economy. You can agree to this with ease because of the seen results, but it was a highly problematic people because even though the economy grew, it was at the expense of the people so it was more like the idea that the railroads and big businesses were helping the economy but exploiting the population.
The second agreeable one is Government has the right to put limits on what businesses can and cannot do, even if those limits lower businesses’ profits. This is because companies sometimes grow too powerful like Rockefeller's company did when he completed his monopoly and it was necessary for the government to limit this in order to prevent harm coming to people from greedy company owners.