The government will see all your transactions. It will become impossible to avoid taxes, buy Bitcoin, or do anything at all without them knowing. Plus, they can cut you out of access to any kind of money if so they wish anytime. How is this not horrible?
Not to mention the fact that you can't really buy anything anymore if you don't have internet or electricity? Or if a bug happens that takes the system down?
This is so obviously bad that's why no one has to be saying these things all the time.