Am I curious? Maybe a little. But I have had a lot of medical issues in my life, and I don't like to dwell on them. So, my choice is to only be tested/treated if I am symptomatic because I assume the MAC is still there, just like the stenosis in my spine, the glaucoma in my eyes, the arthritis everywhere, and the defect in my heart. So I get my regular checkups as recommended for each thing, take the absolutely required meds, exercise, do airway clearance eat well...

As for my lungs, that doesn't mean waiting until I have a horrible cough and green mucus - as soon as I have a hint of respiratory illness, I double down on the airway clearance, start my "emergency" meds as directed if I need to, and call the doc if it doesn't clear up in two weeks. This has kept me healthy for almost 3 years now, my CT's show no changes. And I am not constantly anxious waiting to hear what the latest test shows.

I have the same approach to the rest of my body - I don't ignore potentially serious symptoms, I get them checked out, then get on with life. This is how my Mom & her sister lived - well into their 80's with a plethora of health issues - they are my role models.
But that's just me, with the support of my awesome care team. Everyone needs to do what they are comfortable with.
Sue