We live in a world and a reality of finite resources and we must decide who is to control the decisions regarding distribution of said finite resources. Granted, the pool of resources is vast, but it DOES have limits. Will we allow the distribution of finite resources to be directed by central planners in government or should we allow individuals to decide for themselves which of the resources they wish to pursue, to set their own priorities for the distribution of their labors?
The downside to leaving these decisions to the individual is that some will make poor choices or, due to handicap, have to rely on others for sustenance.
The downside to centrally planning the redistribution is that the central planning board may prioritize in a way that violates your values. It will likely violate a lot of peoples' values. So, those with shared values will band together to try to influence the planners. In all honesty, you wind up first in a situation much like we have today, with the country being run out of Washington with industry groups lobbying the central planning board of our day (Congress) for favorable treatment for their industry.
According to F. A. Hayek's The Road to Serfdom, this is also how the National Socialist Party in Germany came to power in the early part of the 20th Century. We don't need to go back there.
The upside to allowing individuals the Liberty of prioritizing their own life is that you hamstring the central planning board. You give it no power to direct the economic and social lives of the citizens, meaning industries will not gang up to buy favor, but will instead be forced to compete for the individuals favor with their goods and services. If people are assured that they can keep the fruits of their labor and understand that there are real consequences for their failure to participate, you ensure greater participation in the market economy.
The upside of central planning is that your decisions are made for you. Thinking is hard, you know?