This is not necessarily related to the medication. ADD often represents as hyperfocus, to the detriment of the things you should be focusing on. https://en.m.wikipedia.org/wiki/Hyperfocus

Yes absolutely. Not a manager but I noticed this. I think there is also a state of mania involved. While not on these drugs you have a better sense of what is worth effort rather than this euphoric feeling of doing anything for the sake of it.

Adderall and the like are not magic pills that make the most important work/tasks get done first and effectively.

I noticed this in college. My adderall-using friends and roommates would take a pill to study for a test, and sometimes that's exactly what they'd do. But sometimes they'd obsessively clean their room or get into a Wikipedia editing war or corner someone and talk their ear off about a pet topic.

I do this all the time. I have been diagnosed with ADHD, but I'm not on any medication for it. I think you're confusing the treatment and the disease.