It is the duty of the government to regulate the prices of some industries so as to allow fair competition and protect the consumers. Take for example the airline industry, if an airline company will price their tickets lower than the industry standard, it may affect their service and maintenance of their aircrafts hence endagering the lives of their passengers.

But with regards to the telecommunications industry, don't think lives are endangered if SUN cannot maintain their system properly, at the worst it would only cause inconvenience to their subscribers. The big companies are just whining, they are most likely affected by SUN's 24/7.