The car isn’t intelligence.
Not sure why you are implying cars outdid horses intelligence.
Cars are a product of our minds. We have all those self-repair abilities, and we have more intelligence than a horse.
But horses intelligence didn’t let them keep up with what the changing environment, changed by us, needed. So there are less horses.
The rate that horse or human bodies are improving, or our minds, despite human knowledge still advancing, is very slow compared to advances in machines designed specifically for advancement. Initially to accelerate our own advancement.
Now the tech, that was designed to accelerate tech, is taking on a life of its own.
That is how foundational advances happen. They don’t start ahead, but they move ahead because of new advantages.
It is often initially much simpler. But in ways that unlock greater potential.
Machines are certainly much simpler than us. But, much easier to improve and scale.
You recognize the new thing even before it dominates, because in a tiny fraction of the time the old system got to where it is, the new system is already moving much much faster.
If general AI appears before 2047, it will have taken less than 100 years to grow from the first transistor.
People will see it who are older than the first transistor!
Nothing on the planet has ever come close to that speed of progress. From nothing to front runner. By many many many orders of magnitude.
Retric referred to "total computing power".
A horse has trillions of cells, and even one of those cells is doing more biochemical day-to-day computation than your car's automatic transmission does electronically or mechanically.