If a lot more people drove manual transmissions, or at least learned that you can slow down by just raising the accelerator a little rather than hitting the brakes, things would be a lot better. It really doesn't seem like a hard thing to learn.
The other problem is that if you maintain a gap as traffic speeds are slowing, someone will cut in front of you to gain a car length. Then you have to slow down using the brakes.
I drove stick for years, and your parent is right on. And, back in an automatic, I've naturally regressed, I freely admit.