I haven't listened to audiobooks for a long time because I don't drive much. (Don't commute.) I find for podcasts, listening in the car is about the only time they really work for me. Probably because driving requires a level of attention but usually not too much attention.

When I try to listen to podcasts at home my mind usually ends up drifting. And I can't stand having earbuds with music or anything else in my ears when walking. Separates me from my environment too much.

I do one ear when I'm walking or working. I do both if I'm at the gym.

for podcasts, if you use a podcast app like Overcast that supports playback speed adjustments and silence skipping you might find a speed that keeps your attention while still retaining the important stuff.

I wonder if any audiobook apps support that kind of speedup feature?

Personally I have a Goldilocks zone. If I'm just lying on the sofa I start thinking about other things, if I'm doing too much I miss what is happening in the book. However things like walking around town or cleaning the house I really enjoy audiobooks or podcasts.

I walk to and from work - they are perfect for me. My body is engaged so the audiobooks stimulate my brain just enough to allow me to stay locked in.

Same for me. I actually don't want my commute to be shorter than it is now (~30 minutes) because I fall way behind on my podcast queue without it.