The OP sounds overworked or burned out, as opposed to bored. The OP may lack the self-awareness that having a “never-ending to-do-list” is not motivating him, but actually is encouraging procrastination because there are too many things to get done and not enough time, so why do anything? If the OP can’t get the so-called important or fun things accomplished, that’s because he is overwhelmed or a has no energy after work.
Boredom is created by perception. What’s boring for you may not be boring for someone else.
I notice some adults who have leisure time complain to me that they are bored, but that is because they have no focused energy, short or long term goals, and generally are tired from work.
Why not set a handful of simple goals and get them done one at a time?
Many people don’t have the self-awareness to fix problems. Boredom is an emotion that is telling you to do something to make the feeling go away.
Some kids and teens I know will find any excuse to procrastinate. That’s part of their nature, dare I say human nature for adults, too. However, they eventually get bored after they burn out on wasting hours and hours on their iPhones or video games. So the leisure time was ill-spent.
Zen Buddhism is about finding quality in doing “mundane” things like washing dishes or doing the laundry. Even waiting at the airport without using a smart phone could be an opportunity to meditate or reflect. It doesn’t HAVE to be boring if you don’t want it to. Other philosophies focus on living in the present as well.
Many cultures have a mentality that you always have to be “doing” something, move on to a new idea, constantly watch videos and read news, talk, listen, acquire, consume, make money, etc instead of “just being” without the judgement and labeling of emotional experiences as being “productive” or “happy”.