I really hate it when neurologists give those kind of answers.
This doesn't mean that your neurologist is not a wonderful physician and person, it just means that this is the way neurologists look at this, which is (in my opinion) wrong.

It's true that we can't always predict serious and life-threatening complications, but many times early recognition and awareness of physicians and patients for ominous signs can prevent them.

Myasthenic crisis requiring respiratory support rarely just happens with out previous warning signs. There are steps that occur with respiratory muscle weakness. At first there is a feeling of breathing difficulty, compensation with rapid breathing and only after this is exhausted is there a gradual decompensation. At first leading to CO2 retention and only at later stages also hypoxemia, which untreated can lead to irreversible brain damage or even death.

Recognizing those signs on time and resting/cautiously increasing meds. may help avoid further worsening. If not, non-invasive respiratory support can be used in a significant number of patients who have respiratory compromise but a patent airway. Intubation should be kept as a last resort in patients that do not respond to any of those measures.

In the past, patients with significant respiratory muscle involvement would have a trach. so that they could easily receive respiratory support when required in their own home. Nowadays, the same can be done with a face mask as long as the patient is conscious and cooperative and and there is no obstruction of the airway.

Even patients with ALS, can be managed like that continuously for prolonged periods of time. So, obviously someone who has a transient weakness of his/her respiratory muscles and requires respiratory support for a few hours or even days.