Medicine, roads, communications, sewage, water, energy, natural resource management, banking, defence, education, creating and enforcing laws, agriculture, the environment, and whatever social safety is still needed, are things every one needs or may come to need. They should be publicly funded and controlled, with competition allowed beyond the basics. These are things so essential to society and every individual that no one should be kept from utilizing them by price. Indeed, they are the very focus and purpose of civilization beyond the tribe. They should not be ruled by the greed of the market.
When we are spending our time trying to earn enough to provide ourselves with these basics, at costs controlled by the chaos and speculation of the market, we cannot pursue greater goals. The reason it was mostly nobles who made early scientific discoveries was that they were the only ones who could afford the basics and had enough time to pursue education and intellectual experimentation. Discoveries came once a century if we were lucky. Now there are more people able to devote their energy to making discoveries and science has gone exponential (especially in the technology field). There will always be some who milk the system, there are now, so no difference there.
In a world where the essential is the source of profit, too many have to do without while a few have excess. The rich hold the poor hostage. Serve us or wither and die. They can exile us from the very civilization that we help to create. Profits rule instead of the government as the expressed will of the people. The tool of exchange that enabled civilization as one of its parts is now the sole focus of civilization. The Chinese are proof that capitalism and authoritarianism are natural bedfellows. Dictatorships are universal monopolies, organizations without competition run for the benefit of the few or the one at the expense of the many and free choice. Public services provided by truly democratic governments benefit the many and the choice of the many determines their delivery. The will of the people, who make up the so-called free market, determines how much they are willing to pay and what services are desired without companies trying to influence or limit the process. The best capitalists don't invest, they buy up their competition so there are none left and make profit off trading value, not creating real wealth. Keeping the essential services public doesn't prevent competition and innovation in the very large area of non-essential services and products (anything about the basic level), nor the inclusion of such innovations among the essential if they become such. Public services can lead and learn from private. We are the public. We are the private. They should benefit each other. Otherwise we are competing with ourselves in a race off the edge that no one will win.