This is one of the challenges I see with self-driving cars. Driving requires a high level of cognitive processing to handle changing conditions and potential hazards. So when you drive most of your brain is engaged. The impact self-driving cars are going to have on mental stimulation, situational awareness, and even long-term cognitive health could be bigger than we think, especially if people stop engaging in tasks that keep those parts of the brain active. That said, I love the idea of my car driving me around the city while I play video games.
Regarding LLMs, they can also stimulate thinking if used right.