I've improved the handling of a couple of my old 531c bikes by putting chunky carbon forks on them. In fact, one of them was almost transformed with a stiffer fork, but I don't wanna get anyone's hopes up too much. The forks I have on these frames are generic-ish, Asian-made ones with chunky blades and threadless alu steerers. One is branded as Roselli, but the other is an ITM Visia, which is one of the stiffest forks I've had.

I agree that most old steel forks tend to have a bounciness that has obvious pros and cons: tons of comfort, but perhaps with some unwanted flex, and even shimmy tendencies.

I'm not sure how available threaded carbon forks are these days, and the old ones I've used, with steel steerers, tended to have not-so-chunky blades with lots of curve, and they didn't do much to improve the handling of my old steel frames.