The place to get answer to your question is by going to see a qualified Titleist fitter. The fitter will see you on the right track

Varsity golfer? You must have coaching access. Your game can be broken down to if there is low hanging fruit in your game and if equipment is holding back in one facet or another.
We don’t know how well you strike tour irons or if your distance gaps from 6-4 are close to your gapping from 9-7. Is your launch and descent angle too low to hold greens. Or even if your handicap is also due to 3 putts
So, sure, new irons over 20 year old can help your game between the technology, if the faces are too worn, or if the shaft is not ideal. But don’t use us as justification to get new irons. Between coaching and a good fitter they can guide you better than other amateurs sight unseen.