The problem with changing tools to fend off boredom is that it has a very short lifespan. Pretty quickly your brain realizes that it's not learning anything fun

The problem with changing tools to fend off boredom is that it has a very short lifespan. Pretty quickly your brain realizes that it's not learning anything fundamentally new and it protests. Hence fatigue. If possible, it's better to focus on the problem domain and try to make the best of that for entertainment. If not then maybe just accept that it's better to be a bit bored than fatigued.