Well, the bad news is NTM (non-tubercular mycobacteria) is everywhere - in the air, water and soil. Further bad news - there are hundreds of known strains.
The good news is, most strains don't cause infection in humans. And more good news is, even those which do generally only infect a miniscule percent of the population. For something that is everywhere - only one person in 1000 (.1%) develops an NTM infection needing treatment in any year.
Usually, NTM infects people with already unhealthy lungs - those who have Bronchiectasis or Cystic Fibrosis, or people with severely compromised immune systems. And it is treatable. NTM infections like the one mentioned from the guy with the imbedded cactus spine are so rare as to practically be medical oddities.

I'm afraid if I worried about being exposed to NTM, I would need to live in a sterile bubble. Instead, I just use airway clearance and a healthy lifestyle with reasonable precautions to keep MAC and Pseudomonas from settling into my lungs again. It has been working for 3 1/2 years now with no drugs!
Sue