I mean, I agree with you in principle. I think programming a robotic car would be really cool. There's a difference between a foundation (FS, OS, algorithms, etc) and lots of random specialist exposures, though.
I consider myself a generally good programmer. I've been doing it since I was ~6-7, so 15 years now, five of them professionally. I've solved problems in dozens of domains, using probably 20 languages in every major paradigm. But my background is in life sciences, and I've been increasingly feeling like checking out every "cool" technology for the consumption value is a great way to end up a dabbler. It's a little bit of a false dichotomoy, but not entirely. How does this matter to me? is a good first-order heuristic when you're already working 80 hours a week.
That said, I do know the fun of diving into things that seem interesting without necessarily having an immediate application -- I learned most of my languages and technologies that way -- but for some reason, "Programming a Robotic Car" I guess just didn't seem intrinsically interesting as stated. Maybe "I'm never going to use this" is the wrong rationalization for that reaction.