Democracy and democratic ideals demand an open government in which everyone gets one vote. Government secrecy is antithetical to a democracy because there should be openness in how a government deals with people and how it governs. Secrecy simply means more people distrust their own government and the masses should demand answers.
There may have been a time when it could have been argued that secrecy was a necessary part of government. In some ways that argument could still be made today. The problem is that the level of secrecy is so advanced, and the corruption is so deep, that democracy has already been undermined. While citizens and officials debate about the necessity of secrecy, the modern countries will likely maintain their secrecy and we will see as an adjunct to these policies the continued destruction of freedom and a slide into either totalitarianism or social break down, in the face of climate and economic collapse.
Yes, government secrecy is antithetical to democratic government, because the people who vote for a government need to know what their government is doing. If the government is doing secret things, a person needs full information, otherwise they might end up voting for a platform that they do not really support.
I think, at certain times, there is a good place for governent secrecy. Especially in a time of war. For example, take the Cold War for instance. Do you think government transparancy would have been good for the people? Absolutely not. Secrets need to be kept secret sometimes, and it will always be that way.
Any person you meet will have a few secrets that they will never admit. These may be just internal urges or thoughts, all the way to some horrendous act that they have escaped repercussions. Regardless of the nature of the secret, there is always a reason that the person keeps it and validates keeping it. The government is just a group of people who may share secrets that they want to keep from the public. This is a necessary evil that comes with a group of people anywhere. There are some things that the public is better off not knowing. The key is, the government needs to keep the validation of that secret well within reason. This is in case these secrets come out in the open.