If we were to give the state governments more power over spending, it would mean that there would be less centralization. This would be both the good aspect of this action and the bad.
On the good side, giving more power to the states might mean more innovation. Instead of having one system being run in Washington, we could have 50 different systems. It is possible that states would experiment by trying a number of different approaches to various governmental goals. If more approaches were tried, we might have a better chance of finding approaches that worked. In addition, states would have more control and programs would fit better with the attitudes of people in the various states.
But this is also the bad side. If programs were different in various states, people might not be treated fairly. A state might decide that it was going to stop spending on, for example, food stamps. It might feel that this could reduce its taxes and lure more businesses. This would mean that people in this state who needed help would be deprived of that help while people in other states received help. This would not be fair.