[mauvehaus]

All else being equal (initial engineering and handling), an older car has a lot more wear and play in the suspension components. If you haven't spent much time under a car, there's a surprising amount of rubber there in the form of bushings.

Over time, the rubber loses its resilience, and doesn't keep things located as they should be for best handling.

Metal on metal pivots wear as well, springs get less springy, dampers degrade in damping ability, etc.

You're unlikely to notice at regular speeds, apart from getting in a new car and the handling feeling sharper. I presume at high speed and under the sorts of maneuvers one might try as a teenager doing teenager things, the results could vary.

[guywhocodes]

For sure a friend of mine had a very old EPA, it would be about 70 years today if it still exists. It could not go faster than 50kph because the handling combined with imbalance in something almost shook it off the road while going "straight".