The thing stored carefully may still be taking space from something needed now.

Careful storage feels like a decision, but often it is a way of not making one. The item is wrapped, labelled, put somewhere safe, and the question of whether you want it has been postponed rather than answered. Meanwhile the shelf it occupies is the shelf something in current use has to go without. Space is the quietest cost there is, which is why it never shows up in the reckoning.

Open one cupboard and ask what a current need would do with that room. If nothing you use today is short of space, keep it all with a clear conscience; if something is, you have your answer.