You probably don't mean trivial information eg the position of every oxygen atom in my room at this exact moment. But if you eliminate trivial information and concentrate only on useful information, you've turned it into a circular argument - all useful information is inherently useful.

Further, saying that we "must" gather and preserve information ignores opportunity costs. Sure, anything might eventually turn out to be useful, but at some point we have to say the resources invested in disk space would be better used somewhere else.

It sounds more like you're trying to argue that information can never be evil, but you can't even state that meaningfully without making a similar error. Certainly giving information to certain people can be evil (for example, giving Hitler the information on how to make a nuclear bomb).

See this discussion for why I think calling something like "information" good is a bad idea.