My mildly educated guess is: Yes, at least somewhat. Most of the water tank and water course are plastic so probably little to no harm there; just any metal fittings. Since they always emphasize 'distilled' water, I presume water with various minerals in it presents possible problems.
The water circulating in the system is not heated; it is simply picked up by dry moving air blowing over it in the water tank and coursed through the (somewhat heated initially) tubing to the face mask. Just how a saline solution would affect that delivery system is not clear to me. Perhaps saline in the tank would make the water less susceptible to being picked up by the moving air. 🤷 I am not an expert in this conundrum.
MomwithHope says she puts Himalayan pink salt dry in the reservoir (presumably no water) and that works therapeutically for her to help dry her bronchials. Interesting.
My friend, Earl, had that 'Inspire' implanted device installed and, while it took him a little time to adjust to it, he swears by it. Apparently it just stimulates the roots of the tongue to extend a bit.
The CPAP guys recommend distilled water to avoid someone using municipal tap water, which would probably be chlorinated. Snorting evaporated chlorine most likely would work against the first problem. Well water, no water, creek water, would all work OK depending on local humidity, dryness, etc. Ground water heavy in minerals, as in, say, Oklahoma, would slowly build up scale in the tubing. When I’ve seen CPAP used, the balance gets to be waking up with a “normal” nose——not too dry, not too runny.