I doubt the claim of "plenty" of cars coming with ANC built in, but even if all cars came with it, that form of noise cancellation is to national safety standards, specifically for the use of being in a car while on the road. The ANC in Bose headphones are for an entirely different purpose so it's like comparing apples to oranges.
Furthermore, Bose, and basically all other ANC headphones work at isolating and cancelling off the low frequencies you'd typically find in plane engines, which are also most of the time the kinds of frequencies that are also used on a boring road trip where you're the only one on a long stretch of highway (your exact use case). Speech and honks and police alarms aren't things you'd expect to find in this scenario, but early warnings of your car breaking down, or things happening outside of your car that would affect your car do.
Seriously, stop using your headphones while driving. It's illegal in many places for a reason, and you're missing out on far more auditory cues than you realize because your brain is good at moving sensory information into the background when it doesn't deem it as important. Let your brain do its job, it's not that hard to listen to the podcast over your car's BT/AUX connection.
Furthermore, Bose, and basically all other ANC headphones work at isolating and cancelling off the low frequencies you'd typically find in plane engines, which are also most of the time the kinds of frequencies that are also used on a boring road trip where you're the only one on a long stretch of highway (your exact use case). Speech and honks and police alarms aren't things you'd expect to find in this scenario, but early warnings of your car breaking down, or things happening outside of your car that would affect your car do.
Seriously, stop using your headphones while driving. It's illegal in many places for a reason, and you're missing out on far more auditory cues than you realize because your brain is good at moving sensory information into the background when it doesn't deem it as important. Let your brain do its job, it's not that hard to listen to the podcast over your car's BT/AUX connection.