I also don't believe that "Willpower needed to make decisions is a limited resource.", (and in the context) is one reason why todo lists are weighing one down.
The only person I currently found discussing another way of looking at willpower that completely resonated with my experience was Scott Young (https://www.scotthyoung.com/blog/2018/02/09/rethinking-disci...).
Excerpt:
"Needless to say, meditating requires a lot of self-discipline. But is it the kind of self-discipline that gets consumed as a resource?
At first, that answer seemed obvious to me: the longer a meditation session went on, the more willpower I’d need to resist the urge to quit and go do something else. My back and legs would hurt, so I’d want to change my posture. I’d want to daydream about something else, engage in a little mental theatre imagining this scenario or that one. Yet—according to the technique—whenever this happens you’re to remind yourself you’re here to work and shift your focus back onto something happening right now.
As the days wore on, however, I started to notice something about my own self-discipline that seemed to contradict the resource metaphor. Sitting still and doing meditation was hard, but it was hard to the degree to which I was somewhere else. If my attention was fully focused on what I was doing, and not on, say, thinking to myself about how long this will last and when I’ll be free, the act got a lot easier. The longer attention was paid to the meditation without these interruptions, the easier it got.
This suggests a very different model of willpower, one based on attention and mental habit patterns, instead of a consumable resource."