Take chess engines of the "deep blue" era for instance. These engines are stupid, trying millions of moves that are obviously terrible, no human chess player would do that. And yet, this is what worked best, because computers are so good at repetition. Recent development using neural networks made chess engines smarter, but using repetition is still how the beat humans.
What you call "guardrail programming" in another context would genetic algorithms, a technique that has recognized applications. And if you look at videos of genetic algorithms learning to play racing games, it literally looks like a bunch of carnival bumper cars onto the highways, but done well, after some generations, it becomes competent driving, sometimes even record breaking.
It can be expensive, it is often the case for LLMs, so you may want to try to be a bit smarter at first to spare some resources, but to me, it is just using computers as intended.
Not difficult to see why the employees of AI firms are thrilled with it though, eh?
I like the analogy.
I guess this is why we got this before cars sold without steering wheels: literal guardrails on the literal roads are somewhat more expensive, especially for the people who keep bouncing off them on the way to their destination.
Also, where the guardrails are absent: oh look, felonies. https://www.google.com/search?q=ai+hacks+company&tbm=nws