I respect ALL of the guys that have posted in this Topic...but yet my comments will disagree with SOME of what they have said.
Over 40 YEARS of observing rust on everything from tools...to fishing tackle...to vehicles...my HUMBLE opinion is that there are 2 basic kinds of rust...one that originates from underneath metal plating / paint...and then there's surface rust.
I have acquired MANY lures over the year where I simply took a detail wire brush to them and cleaned them...and never had a problem.
At the same time though...there have been SOME lures that the hooks didn't look right to me after the brushing.
THEN...of course...there's SOME folks that believe that your rod....and EVERYTHING from the line on down to the lure...is basically a small crane...and that you can lift a +5 lb fish out of the water with it
Bottom LINE to ME is...take a small wire brush to the hooks and hardware...then look at them with a magnifying glass.
IF you don't like what you see..then replace.
I've seen 75 year old hooks that had surface rust catch decent fish...