https://en.wikipedia.org/wiki/Seeing_Like_a_State
When the state is more likely to cause you problems than help you out, you want them to be bad at it. The corrupt cop going on a fishing expedition to try to bust you for something because you're dating his ex, who can't find anything because it's "spread out, fragmented, stored with multiple conflicting versions" -- that's what you want to happen.
It's also not just about the government. If you give everyone a government ID which is easy to use over the internet, private companies will then demand that you use it over the internet and use it as a tracking ID. Which is the evil to be inhibited.