I often choose 144p for low bandwidth scenarios. It is very similar to a good quality audio-only stream in terms of size, but you get the added benefit of looking at the speaker even if that's a glance every 45 mins. Same for battery life, you save that too.

Also 144p is somehow so peaceful and relaxing to watch, you don't get distracted with all the shiny colors and intricate details in the video and can just listen and not have your mind focus on some random stuff.