Doing hard things is hard, and that means I won't be thinking about the other stuff I have to do. I'm more apt to miss a text from my family when I'm running or writing a document than when I'm vibe coding, because the effort is all-encompassing. Subconsciously, that's stressful, so I steer away from it.
Habits help here, because with enough repetition, I learn that it's OK to disappear for an hour to do the thing. But the real issue is getting the meta-organization of my life right enough that I'm not scared to shut down my ambient executive function for that hour. This shows up as both "I'm too busy to do the hard thing" and "I'm too tired to do the hard thing."
Slowing down isn't the answer, but it's been pretty transformative to notice that that's what I'm worried about.