MAC diagnosis with w/limited continued symptoms

My mother is 86. A year ago, she had a sputum test, which confirmed the diagnosis of MAC. She had a chronic cough and was losing weight. The pulmonologist recommended a sputum test, and the diagnosis was confirmed. After the bronchoscopy, her coughing symptoms subsided, and we were told that this was probably due to the procedure removing the mucus from her lungs. We have also consulted with an infectious disease doctor who recommended monitoring her with scans every 3 months. We connected with a nutritionist about 6 months ago, who helped her stabilize the weight loss, but with minimal weight gain. She just saw her pulmonologist today, and the report was that the disease was spreading, but not at an alarming rate. His initial recommendation today was to reconnect with the ID doctor about treatment. My pushback was, and still is, that she is not presenting with symptoms. She doesn't cough and may be slower and short of breath, but only when she is doing too much, like using stairs. She doesn't require assistance, but she gets tired more easily. But she is 86. The doc agreed that we would wait another 3 months to reevaluate. She has had a history of gastrointestinal issues that have been resolved (constipation), and she is currently being treated for glaucoma, liver disease, and has stage 3 kidney disease. Our concern is the side effects of the multiple antibiotics on her organs and her ability to tolerate them while being able to maintain and possibly gain her weight back. She lost 20 pounds over the past 1 1/2 years (from 130# to 112# now). Her quality of life is very good right now but we were told that could change at any time and the antibiotics might be that much harder to tolerate if she is having respiratory issues as well. Not sure what question I have for you all except, does anyone have any experience with putting off the regimen at an advanced age like her? Just looking to see if we are being reasonable. In general, her pulmonologist and ID doctors have been very straightforward with us, but nobody knows what life will be like when this goes untreated if the symptoms start. Thank you for reading.