In my garage I've got a Cummins 200 that hasn't been used since 1969, a Lincoln Continental Mark IV that hasn't been driven since 1989, and a roll of 1" steel cable that dates back to the last time we owned a cable run excavator...say early 60's?

IMO, nothing wrong with hanging onto old stuff, if you have the room to do it and can keep it organized. I've had stuff come in handy that hadn't been used for at least 10 years prior (like a 3" water pump during hurricane Floyd).

The exception to that, for me, is perishable items. I don't typically hang on to expired food, medicine, chemicals, ect. Sure, it might be good for a while after the expiration date, but I'd rather just replace it with fresh stuff.